Page 10
¦ ¦ ¦ Millimeters ¦ ¦ ¦ Manual Transaxle or Transmission ¦ ¦ ¦ MA PFI Mass Air Sequential Port Fuel Injection system ¦ ¦ ¦ MA or MAF Mass Airflow ¦ ¦ ¦ Mass Air Flow sensor ¦ ¦ ¦...
Page 13
¦ ¦ ¦ Torque Converter Clutch ¦ ¦ ¦ TCCS Toyota Computer Control System ¦ ¦ ¦ Top Dead Center ¦ ¦ ¦ TDCL Total Diagnostic Communication Link ¦ ¦ ¦ Thick Film Ignition system ¦ ¦ ¦ Top Gear Switch (cancels SIL in top gear) ¦...
METRIC CONVERSIONS 1993 Jeep Cherokee GENERAL INFORMATION METRIC CONVERSIONS METRIC CONVERSIONS Metric conversions are making life more difficult for the mechanic. In addition to doubling the number of tools required, metric-dimensioned nuts and bolts are used alongside English components in many new vehicles. The mechanic has to decide which tool to use, slowing down the job.
meter long with force of one Newton applied). Some conversions are: A meter kilogram is about 7.2 foot pounds. A foot pound is about 1.4 Newton-meters. A centimeter kilogram (cmkg) is equal to .9 inch pounds. PRESSURE Pressure is another complicated measurement. Pressure is described as a force or weight applied to a given area.
MAINTENANCE INFORMATION 1993 Jeep Cherokee 1989-95 MAINTENANCE Jeep Maintenance Information Cherokee, Wagoneer (1989-90) * PLEASE READ THIS FIRST * NOTE: For scheduled maintenance intervals and the related fluid capacities, fluid specifications and labor times for major service intervals, see SCHEDULED SERVICES article.
Page 22
Fig. 2: Hoist Lift Point Locations Courtesy of Chrysler Corp. NOTE: For more information regarding jacking and hoisting refer to the JACKING & HOISTING article in the...
Page 23
WHEEL ALIGNMENT section. Fig. 3: Brake Caliper Lubrication Points Courtesy of Chrysler Corp. NOTE: For more information regarding brake maintenance refer to the BRAKE SYSTEM article in the BRAKES section.
Page 24
Fig. 4: Front Disconnect Housing Lubrication Point Courtesy of Chrysler Corp. IDENTIFICATION LABEL LOCATIONS...
Page 26
Weatherstrip ......Silicone Spray Lubricant (1) - DO NOT use Dexron-III ATF, Clutch chatter can result. (2) - SAE 10W-30 SH/CD ECII is preferred. (3) - DO NOT use heavier weight lubricant, as it will cause axle engagement difficulties, use only SAE 80W-90 lube. (4) - Add 4 ozs.
1993 Tighten lug nuts in crisscross pattern to 95 ft. lbs. (129 N. 1994-96 Tighten lug nuts in crisscross pattern to 85-110 ft. lbs. (115-149 N.m). Fig. 6: Wheel Locking Nut Location Courtesy of Chrysler Corp. BATTERY SPECIFICATIONS CAUTION: When battery is disconnected, vehicles equipped with computers may lose memory data.
Page 29
CAUTIONS & WARNINGS SUPPLEMENTAL RESTRAINT SYSTEM (SRS) AIR BAG SYSTEM NOTE: See the AIR BAG RESTRAINT SYSTEM article in the ACCESSORIES/SAFETY EQUIPMENT Section. The SRS has no user-servicable parts. Always have servicing done by an authorized dealer. When performing maintenance on air bag equipped vehicles always observe proper safety precautions.
Page 30
COOLANT (PROPYLENE-GLYCOL FORMULATIONS) CAUTION: To avoid possible damage to vehicle use only ethylene-glycol based coolants with a mixture ratio from 44-68% anti-freeze. DO NOT use 100% anti-freeze as it will cause the formation of cooling system deposits. This results in coolant temperatures of over 300 F (149 C) which can melt plastics.
been submerged in water. Water can enter through the axle vent hole and contaminate the lubricant. COMMAND-TRAC (4WD) CAUTION: NEVER operate a Command-Trac vehicle in 4WD on dry, hard-surfaced roads for a sustained period. Use 4L only when needed for added pulling power. Operating vehicle in 4WD mode on such roads will cause stress and possible damage to components, as well as make shifting difficult.
Page 32
2WD models and a $150.00 deductible on 4WD models applies to each repair visit. Powertrain Warranty also covers cost of towing to nearest Jeep Dealer if vehicle cannot be driven due to failure of a covered powertrain part. ANTI-CORROSION PERFORATION WARRANTY Warrants the sheet metal parts of the vehicle against perforation (rust-through) due to corrosion.
Page 33
excluded) which have proven defective in material and workmanship during normal use. Warranty repairs (parts and labor) will be made by the dealer at no charge. Beginning at warranty start date, warranty lasts for 36 months or 36,000 miles, whichever occurs first. Warranty covers every Chrysler supplied part of vehicle EXCEPT its tires and OKI cellular telephone (Tires and Telephone are covered by seperate warranties offered by their manufacturers).
3 years or 50,000 miles, whichever occurs first. Warranty begins at warranty start date and lasts for a period of 3 years or 50,000 miles, whichever occurs first. The following emission-related parts are warranted for 7 years or 70,000 miles, whichever occurs first, and will be repaired or replaced by manufacturer if found to be defective in material or workmanship: Catalytic Converter, Intake Manifold, Carburetor, Throttle Body, Injectors, Fuel Tank, Exhaust Manifolds (4.0L).
Page 41
Fig. 12: Fuse Panel Identification (1993-96) Courtesy of Chrysler Corp. Fuse & Circuit Breaker Identification...
Page 42
1 - 25 Amp (Natural) Rear Window Wiper, Washer 2 - 15 Amp (Lt. Blue) Radio, Cigar Lighter, Dome Lamp (1993) 3 - Not Used 4 - 15 Amp (Lt. Blue) Flash to Pass 5 - 25 Amp (Natural) Blower Motor 6 - 30 Amp (Circuit Breaker) Power Windows 7 - 2 Amp (Pink)
Page 43
Fig. 13: Relay Block Identification (1993-96 Models) Courtesy of Chrysler Corp. Relay Identification...
Page 44
1 - Illuminated Entry Relay (1993-94) Not Used (1995-96) 2 - Horn Relay (1993-94) Dual Flasher Relay (1995-96) 3 - Rear Window Defogger Relay 4 - Not Used 5 - Not Used (1993-94) Horn Relay (1995-96) 6 - Not Used 7 - Not Used 8 - Radio Illumination Relay 9 - Power Door Lock (Unlock) Relay...
Page 45
13 - 15 Amp (Blue) Auxilliary Lamps - Fog Lamps, Underhood Lamps 14 - 20 Amp (Yellow) Engine Controller 15 - 20 Amp (Yellow) Aux. Cooling Fan 16 - 10 Amp (Red) Ignition Off Draw (1993) Radio/Clock Memory, Ignition Off Draw, Dome Courtesy(1994-96) Relay Identification A - Aux.
SCHEDULED SERVICES 1993 Jeep Cherokee 1989-96 MAINTENANCE Jeep Maintenance & Service Intervals Jeep; Cherokee (1989-96), Wagoneer (1989-90) * PLEASE READ THIS FIRST * NOTE: All SERVICE SCHEDULES are listed for normal service vehicles. If vehicle is operated under severe service...
Chrysler Mopar parts catalog only. DO NOT mix components in this mechanically-fired airbag with components from ANY electrically-fired airbag system. WARNING: The fasteners, screws and bolts used in this air bag system have a special coating on them and are specifically designed for use with this air bag system.
Page 48
WARNING: When battery is disconnected, vehicles equipped with computers may lose memory data. When battery power is restored, driveability problems may exist on some vehicles. These vehicles may require a relearn procedure. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION section. REPLACING BLOWN FUSES Before replacing a blown fuse, remove ignition key, turn off all lights and accessories to avoid damaging the electrical system.
Page 49
hard-surfaced roads for a sustained period. Use 4L only when needed for added pulling power. Operating vehicle in 4WD mode on such roads will cause stress and possible damage to components, as well as make shifting difficult. To reduce shifting effort, drive vehicle in Reverse for a few feet, or drive off hard-surfaced road momentarily to allow tire slippage.
WHEEL & TIRE WARNINGS CAUTION: Replacing original tires with different size tires may result in false speedometer and odometer indications. Check with dealer before using different size tires on vehicle. CAUTION: Ensure all 4 wheels on vehicle have same tire size, type and circumference in order to provide proper vehicle handling.
Fig. 1: Service Point Locations (Typical) Courtesy of Chrysler Corp. ADDITIONAL SERVICE INFORMATION...
Page 52
Fig. 2: Hoist Lift Point Locations Courtesy of Chrysler Corp. NOTE: For more information regarding jacking and hoisting refer to the JACKING & HOISTING article in the...
Page 53
WHEEL ALIGNMENT section. Fig. 3: Brake Caliper Lubrication Points Courtesy of Chrysler Corp. NOTE: For more information regarding brake maintenance refer to the BRAKE SYSTEM article in the BRAKES section.
Page 54
Fig. 4: Front Disconnect Housing Lubrication Point Courtesy of Chrysler Corp. IDENTIFICATION LABEL LOCATIONS...
Fig. 5: Identification Label Locations Courtesy of Chrysler Corp. SEVERE & NORMAL SERVICE DEFINITIONS NOTE: Use the Severe Service schedule if the vehicle to be serviced is operated under ANY (one or more) of these conditions: Service is recommended at mileage intervals based on vehicle operation.
Page 56
subjected to severe service. See SEVERE & NORMAL SERVICE DEFINITIONS. This service is to be performed in addition to the normal services listed in the NORMAL MAINTENANCE SERVICE SCHEDULES. SEVERE SERVICE CONDITIONS/ACTIONS TABLE ¡ £ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¥ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¥ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¥ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¢ ¤ ¦ §...
Page 62
§ § § § (1) - DO NOT use Dexron-II ATF, Clutch chatter can result. § § (2) - SAE 10W-30 SH/CD is preferred. § § (3) - DO NOT use heavier weight lubricant, as it will cause axle § §...
Page 64
§ § (1) - DO NOT use Dexron-II ATF, Clutch chatter can result. § § (2) - SAE 10W-30 SH/CD is preferred. § § (3) - DO NOT use heavier weight lubricant, as it will cause axle § § engagement difficulties, use only SAE 80W-90 lube. §...
Page 87
§ § (1) - DO NOT use Dexron-II ATF, Clutch chatter can result. § § (2) - SAE 10W-30 SH/CD is preferred. § § (3) - DO NOT use heavier weight lubricant, as it will cause axle § § engagement difficulties, use only SAE 80W-90 lube. §...
Page 88
§ § (6) - Fill to bottom edge of filler plug hole. § § (7) - Add 5 ozs. of gear lubricant through indicator switch hole. § § (8) - If equipped with TRAC-LOK, add 4 ozs. of Limited-Slip § §...
TROUBLE SHOOTING - BASIC PROCEDURES 1993 Jeep Cherokee GENERAL TROUBLE SHOOTING * PLEASE READ THIS FIRST * NOTE: This is GENERAL information. This article is not intended to be specific to any unique situation or individual vehicle configuration. The purpose of this Trouble Shooting information is to provide a list of common causes to problem symptoms.
Page 107
Engine overheated See ENGINE COOLING SYSTEM article Engine oil too heavy Check that proper viscosity oil is used Poor battery-to-starter Check that all connections between battery and starter are clean and tight Current draw too low or See Bench Tests in too high STARTER article Bent armature, loose pole...
Page 112
sluggish See DISC BRAKES or BRAKE SYSTEM Master cylinder piston stuck See MASTER CYLINDERS or BRAKE SYSTEM Brake fade due to incorrect pads for linings Replace pads or linings Linings or pads glazed Replace pads or linings Worn drums Reface or replace drums ¡...
Parking Brake cables frozen See DRUM BRAKES BRAKE SYSTEM Incorrect installation of inboard disc pad Remove and replace correctly Power booster output rod too long See POWER BRAKE UNITS BRAKE SYSTEM Brake pedal not returning See DISC, DRUM BRAKES freely BRAKE SYSTEM ¡...
Page 114
Water Pump Malfunction Replace Water Pump Fan Clutch Malfunction Replace Fan Clutch Retarded Ignition Timing Reset Ignition Timing Cooling Fan Malfunction Test Cooling Fan/ Circuit Cooling Fan Motor Malfunction Test Fan Motor Cooling Fan Relay Malfunction Test Fan Relay Faulty Radiator Cap Replace Radiator Cap Broken/Slipping Fan Belt Replace Fan Belt...
Page 126
Low fuel pressure Test pressure regul- ator and fuel pump, check for restricted lines and filters No distributor reference Repair ignition pulses system as necessary Open coolant temperature Test sensor and sensor circuit wiring Shorted W.O.T. switch in Disconnect W.O.T. T.P.S.
Page 127
or alcohol Intermittent ECM ground Test ECM ground connection for resistance Restricted air cleaner Replace air cleaner Restricted exhaust system Test for exhaust manifold back pressure Poor MAF sensor signal Check leakage between sensor and manifold Poor VSS signal If tester for ALCL hook-up is available check that VSS reading matches...
Page 130
Ignition switch faulty Adjust or replace or misadjusted ignition switch Open circuit between Check and repair wires starter switch ignition and connections as terminal on starter relay necessary Starter relay or starter See Testing in STARTER defective article Open solenoid pull-in See Testing in STARTER wire article...
Page 147
In certain conditions, the pitch of the exhaust gases may sound like gear whine. At other times, it may be mistaken for a wheel bearing rumble. Tires, especially radial and snow, can have a high-pitched tread whine or roar, similar to gear noise. Also, some non-standard tires with an unusual tread construction may emit a roar or whine.
Page 148
axle backlash. If backlash is one inch or less, drive axle is not the source of clunk noise. Bearing Whine Bearing whine is a high-pitched sound similar to a whistle. It is usually caused by malfunctioning pinion bearings. Pinion bearings operate at drive shaft speed. Roller wheel bearings may whine in a similar manner if they run completely dry of lubricant.
Page 150
problem symptoms. For model-specific Trouble Shooting, refer to SUBJECT, DIAGNOSTIC, or TESTING articles available in the section(s) you are accessing. BASIC FWD AXLE SHAFTS & CV JOINTS TROUBLE SHOOTING CHART ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ CONDITION POSSIBLE CAUSE ¡...
Page 151
knuckles steering linkage Rack and pinion mounting Tighten all mounting loose bolts Rack and pinion out of See adjustment in adjustment STEERING article Tie rod end loose Tighten and check steering linkage Excessive Pitman shaft-to- Repair as necessary ball nut lash ¡...
Page 155
Reaction ring sticking See POWER STEERING GEAR in housing head article Steering pump internal See POWER STEERING PUMP leakage article Steering gear-to-column See STEERING COLUMN misalignment article Lack of lubrication in Service front suspension linkage Lack of lubrication in Service front suspension ball joints ¡...
Page 156
Free play in pot coupling See POWER STEERING PUMP article Steering gear coupling See POWER STEERING PUMP loose on shaft article Steering disc mounting Tighten or replace if bolts loose necessary Coupling loose on worm Tighten or replace if shaft necessary Improper sector shaft See POWER STEERING GEAR...
Page 157
No Power, Column pot coupling See STEERING COLUMN Right Turns bottomed article Right turn reaction seal See POWER STEERING GEAR "O" ring worn article Right turn reaction seal See POWER STEERING GEAR damaged article Internal leakage through See POWER STEERING GEAR piston end plug article Internal leakage through...
Page 158
Column not correctly See STEERING COLUMNS aligned article Broken lower joint Replace joint Horn contact ring not See STEERING COLUMN article Bearing not lubricated See STEERING COLUMN article Shaft snap ring not Reseat or replace snap properly seated ring Plastic spherical joint See STEERING COLUMN not lubricated article...
Page 161
Air in system Bleed air from system Undercoating on shocks Remove undercoating ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ Car Leans or Loose stabilizer bar See SUSPENSION...
Page 162
Mismatched tires See WHEEL ALIGNMENT Broken or sagging spring See SUSPENSION section Broken torsion bar See SUSPENSION section Power steering valve not See STEERING section centered Front alignment out of See WHEEL ALIGNMENT tolerance section Defective wheel bearing See WHEEL BEARINGS in SUSPENSION section Uneven sway bar links See SUSPENSION section...
Page 165
4.0L On machined surface, on right side of cylinder block, between cylinders No. 2 and No. 3. 5.2L On machined surface, on left front corner of cylinder block, below cylinder head.
Page 167
C - SPECIFICATIONS 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. - Service & Adjustment Specifications Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler INTRODUCTION Use this article to quickly find specifications related to servicing and on-vehicle adjustments. This is a quick-reference article for when you are familiar with an adjustment procedure and only need a specification.
Wrangler ......3.3 Pts. (1.5L) Model 249 ......3.0 Pts. (1.4L) Selec-Trac 242 ......3.0 Pts. (1.4L) (1) - Fluid capacities listed are approximate. Always fill to FULL mark. (2) - Includes oil filter. (3) - Drain and refill capacity only. Does not include torque converter.
Fig. 3: Firing Order & Distributor Rotation (5.2L) Courtesy of Chrysler Corp. IGNITION TIMING Vehicles are equipped with Powertrain Control Module (PCM) computerized ignition. PCM controls ignition timing. No adjustment is possible. DISTRIBUTOR SPECIFICATIONS Vehicles are equipped with Powertrain Control Module computerized ignition.
Page 173
All models are equipped with hydraulic valve lifters. No adjustments are required. IGNITION TIMING All Jeep vehicles are equipped with Powertrain Control Module (PCM) computerized ignition system. PCM controls ignition timing. Adjustment is not required or possible. IDLE SPEED & MIXTURE All Jeep vehicles are equipped with Powertrain Control Module computerized ignition system.
E - THEORY/OPERATION - 2.5L & 4.0L 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. Theory & Operation Jeep; Cherokee, Grand Cherokee, Wrangler INTRODUCTION This article covers basic description and operation of engine performance-related systems and components. Read this article before diagnosing vehicles or systems with which you are not completely familiar.
Page 175
not receive an A/C select signal. When A/C function is selected (A/C switch on), the A/C request signal provides information to the PCM from the A/C temperature control thermostat (evaporator switch). This signal indicates evaporator temperature is in the proper range for A/C operation.
Page 176
high (5 volts). When the metal between the slots is aligned with sensor, output voltage goes low (.3 volts). This high/low voltage signal is sent to PCM each time one of the slots passes the crankshaft position sensor. The PCM uses this information to determine when to energize the injectors for fuel delivery to the proper cylinders.
Page 177
Power Steering Switch On 2.5L with power steering, a power steering switch is used. The switch is located on pressure line, next to power steering pump. The power steering switch sends a signal to PCM when system pressure rises to greater than 250-300 psi (17.6-21.1 kg/cm ) when engine RPM is low.
The vehicle speed sensor is located on transaxle extension housing (2WD models) or on transfer case extension housing (4WD models). The PCM uses vehicle speed (distance) sensor to detect if vehicle is moving and at what speed it is moving. The sensor is an 8-pole switch which provides a pulse or switching rate, proportional to vehicle speed, to the PCM.
Malfunction Indicator Light (MIL) See SELF-DIAGNOSTIC SYSTEM. Radiator (Cooling) Fan Relay See MISCELLANEOUS CONTROLS. Serial Communication Interface Transmit See MISCELLANEOUS CONTROLS. Service Reminder Indicator (SRI) See EMISSION SYSTEMS. Speed (Cruise) Control Solenoids See MISCELLANEOUS CONTROLS. Upshift Indicator Light See MISCELLANEOUS CONTROLS. FUEL SYSTEM FUEL DELIVERY Automatic Shutdown Relay...
resistor. At wide open throttle, fuel pump receives voltage through the ballast resistor by-pass relay, which speeds up fuel pump to compensate for higher fuel demand. Fuel Pump (Electric) All models are equipped with a gear/rotor type electric pump. Pump is driven by a permanent magnet, 12-volt electric motor. The in- tank pump is an integral part of the fuel gauge sending unit.
All engines use a sequential port fuel injection system. This means that the injectors have a specific firing order and fuel injection is timed to piston movement. The spark plugs and injectors are fired in the same order: 1-3-4-2 on 2.5L and 1-5-3-6-2-4 on 4.0L. In order for the PCM to fire the injectors in a specific order timed to crankshaft and piston movement, it has to establish a reference point.
Page 182
engine speed by controlling the amount of air allowed to enter the intake manifold and is mechanically operated by the accelerator cable. The PCM and IAC motor adjust engine idle by regulating the size of an air by-pass passage that routes air past the closed throttle plate.
EMISSION SYSTEMS CRANKCASE VENTILATION (CCV) SYSTEM Engines on all models use a crankcase ventilation system. The CCV system performs the same function as a conventional PCV system, but does not use a vacuum controlled valve. On 2.5L engine, a fitting on the driver’s side of the cylinder head cover contains a metered orifice that is connected to manifold vacuum.
rollover. The valve consists of a plunger, spring, orifice and guide plate. The valve is normally open, allowing fuel vapors to vent to the canister where they are stored. If bottom of plunger is contacted by sloshing fuel in fuel tank, the plunger seats in the guide plate, preventing liquid fuel from reaching the evaporative canister.
Page 185
When engine coolant temperature reaches 217 ¡ F (103 ¡ C), PCM supplies radiator cooling fan relay with a ground path which closes the radiator cooling fan relay contacts and allows battery voltage from the ignition switch to reach radiator cooling fan motor. SERIAL COMMUNICATIONS INTERFACE TRANSMIT The Serial Communications Interface (SCI) transmit circuit is the serial data circuit that is used when diagnosing vehicle with...
1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. 2.5L & 4.0L Basic Diagnostic Procedures Jeep; Cherokee, Grand Cherokee, Wrangler INTRODUCTION The following diagnostic steps will help prevent overlooking a simple problem. This is also where to begin diagnosis for a no-start condition.
Exhaust System Backpressure The exhaust system can be checked with a vacuum or pressure gauge. Remove O2 sensor. Connect a 0-5 psi pressure gauge and run engine at 2500 RPM. If exhaust system backpressure is greater than 1 3/4 - 2 psi, exhaust system or catalytic converter is plugged. If a vacuum gauge is used, connect vacuum gauge hose to intake manifold vacuum port and start engine.
Page 188
¢ RELEASE. Connect a 0-60 psi (0-4.2 kg/cm ) fuel pressure gauge to the pressure test port fitting on fuel rail. 2) Remove fuel pump relay (located in power distribution center). Using a jumper wire, connect terminals No. 30 and 87. See Fig.
Page 189
is present at relay terminals No. 30 (battery) and 87 (fuel pump), and at fuel pump. See Fig. 2. 3) If fuel pump still does not work, check ballast resistor (Cherokee only) and fuel pump ground. If ballast resistor and ground are okay, replace fuel pump.
Page 190
SECONDARY SPARK Spark Test 1) Remove coil wire from distributor cap. Hold end of cable about 1/4" from ground. Crank engine. Spark should be present and constant. If spark is not present and constant, check coil and coil wire resistance. Perform IGNITION PRIMARY test under IGNITION CHECKS. 2) If coil wire spark is present, ensure spark reaches spark plugs.
G - TESTS W/CODES - 2.5L & 4.0L 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp 2.5L & 4.0L Self-Diagnostics Jeep; Cherokee, Grand Cherokee, Wrangler NOTE: For Grand Cherokee with 5.2L engine, see G - 5.2L TESTS W/ CODES article in the ENGINE PERFORMANCE Section.
a small screwdriver, wrapped in shop towels, push test port valve in to relieve fuel pressure. Absorb spilled fuel with shop towels. Remove shop towels and dispose of properly. Install protective cap on pressure test port. Fig. 1: Releasing Fuel Pressure Courtesy of Chrysler Corp.
Page 195
tests: Go to TEST NS-1A (QUALIFYING NO START CONDITION) if a no start condition exists or engine stalls after start-up. Perform indicated VERIFICATION TEST after repairs have been made. Go to TEST FC-1A (CHECKING FOR FAULTS) if engine runs but has performance problems.
Fig. 2: Locating Diagnostic Connector (Cherokee & Wrangler) Courtesy of Chrysler Corp. Fig. 3: Locating Diagnostic Connector (Grand Cherokee) Courtesy of Chrysler Corp. CLEARING FAULTS...
Page 197
CAUTION: When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION Section before disconnecting battery. 1) If DRB-II is not available, go to step 3). If DRB-II is available, press "1"...
Page 198
2) Copyright information and diagnostic program version will appear on screen for a few seconds. After a few seconds DRB-II menu will appear. At FUEL/IGN MENU, press "5" (ADJUSTMENTS) key. Press ENTER key. At ADJUSTMENTS menu, press "4" (SRI MEMORY CHK) key. Press ENTER key.
If vehicle mileage is not within specification, go to next step. 5) Press NO key. DRB-II will display ENTER MILEAGE SHOWN ON INSTRUMENT PANEL (USE ENTER TO END) XXXXXXX. Enter vehicle mileage. DO NOT enter tenths. When correct vehicle mileage is entered, press ENTER key.
Page 200
DRB-II displays O2S STAYS AT CENTER. Condition is: no rich or lean signal detected from oxygen sensor input. Code 21 DRB-II displays O2S SHORTED TO VOLTAGE. Condition is: oxygen sensor input voltage maintained at more than normal operating range. Code 22 DRB-II displays ECT SENSOR VOLTAGE TOO LOW.
Page 201
circuit. Code 42 DRB-II displays AUTO SHUTDOWN RELAY CONTROL CIRCUIT. Condition is: open or shorted condition detected in Auto Shutdown (ASD) relay circuit. Code 42 DRB-II displays NO ASD RELAY VOLTAGE SENSE AT PCM. Condition is: Powertrain Control Module (PCM) did not receive message in Auto Shutdown (ASD) relay circuit.
Page 202
by-pass relay circuit. CAUTION: When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION Section before disconnecting battery. CONNECTOR IDENTIFICATION CONNECTOR IDENTIFICATION DIRECTORY TABLE ¡...
Page 203
Fig. 5: Identifying Coolant Temperature Sensor Connector Terminals Courtesy of Chrysler Corp. Fig. 6: Camshaft & Crankshaft Position Sensor Connector Terminal ID Courtesy of Chrysler Corp.
Page 204
Fig. 7: Identifying Engine Controller Connector Terminals Courtesy of Chrysler Corp. Fig. 8: Identifying Engine Diagnostic Connector Terminals Courtesy of Chrysler Corp. ENGINE DIAGNOSTIC CONNECTOR TERMINAL IDENTIFICATION...
Fig. 15: Testing Fuel Pump Relay Courtesy of Chrysler Corp. SELF-DIAGNOSTIC TESTS...
Page 210
NOTE: For Grand Cherokee with 5.2L engine, see G - 5.2L TESTS W/ CODES article in the ENGINE PERFORMANCE Section. TEST FC-1A - CHECKING FOR FAULTS NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION at beginning of article. For wiring diagrams, see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section.
Page 211
INTERNAL PCM FAILURE ........... SPEED CONTROL SOLENOID CIRCUITS ........ (1) - See ALTERNATORS article in the ELECTRICAL Section. ¢ (2) - Check cooling system if engine temperature does not reach 176 ¢ C) after driving 20 minutes. This code may set in error during very cold slow speed driving.
Page 212
resistance is more than 5 ohms, repair open in Black/Light Blue wire. Perform TEST VER-1. 11) If resistance is less than 5 ohms, disconnect PCM connector. Inspect PCM sensor connector for damaged or pushed-out terminals. Repair as necessary. Perform TEST VER-1. If PCM connector terminals are okay, go to next step.
Page 213
SYCN SIGNAL AT PCM, go to step 5). 3) NO CAM SYNC SIGNAL AT PCM fault sets if Powertrain Control Module does not see Camshaft Position (CMP) sensor signal with Crankshaft Position (CKP) signal present. Possible causes are: failed CMP sensor, open or shorted CMP sensor signal circuit (Tan/Yellow wire on XJ and YJ bodies or Gray/Black wire on ZL body), open CMP sensor 8- volt supply circuit (Orange wire on XJ and YJ bodies or White/Black wire on ZJ body), open CMP sensor ground circuit (Black/Light Blue...
Page 214
2) Using an external ohmmeter, check resistance of 8-volt supply circuit (Orange wire on XJ and YJ bodies or White/Black wire on ZJ body) between CMP sensor connector harness side and PCM connector terminal No. 7. If resistance is more than 5 ohms, repair open in Orange wire on XJ and YJ bodies or White/Black wire on ZJ body.
Page 215
2) Using DRB-II, read MAP sensor voltage. If voltage is less than 1.2 volts, go to step 5). If voltage is more than 1.2 volts, wiggle MAP sensor connector and wiring harness while watching DRB-II display. If MAP sensor voltage changes, repair connector or wiring harness as necessary.
Page 216
replace MAP sensor. Perform TEST VER-1. 5) If MAP sensor voltage is more than one volt, move jumper wire from MAP sensor connector, ground circuit (Black/Light Blue wire) to an engine ground. Using DRB-II, read MAP sensor voltage. 6) If MAP sensor voltage is less than one volt, repair open in Black/Light Blue wire.
Page 217
signal circuit (White/Orange wire) between VSS connector harness side and PCM connector terminal No. 47. If resistance is more than 5 ohms, repair open in White/Orange wire. Perform TEST VER-1. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-1. TEST FC-7B - NO VEHICLE SPEED SENSOR SIGNAL NOTE: For connector terminal identification, see CONNECTOR...
Page 218
5) If resistance is less than 5 ohms, connect a jumper wire between oxygen sensor signal circuit (Black/Dark Green wire on XJ and YJ bodies or Black/Orange wire on ZJ body) and battery positive terminal. Using DRB-II, read oxygen sensor voltage. If oxygen sensor voltage is more than one volt, replace oxygen sensor.
Page 219
2) O2S STAYS ABOVE CENTER (RICH) fault sets if oxygen sensor output voltage stays at more than .5 volt, but less than 1.2 volts, without changing for more than 8 minutes. Possible causes are: high fuel pressure, other engine sensor calibration failures, ignition system failure, oxygen sensor failure or fuel contamination.
Page 220
voltage. If voltage is more than 4.5 volts, go to step 4). If voltage is less than 4.5 volts, while observing DRB-II, wiggle wiring harness from ECT sensor to Powertrain Control Module (PCM). If voltage changes, repair wiring harness as necessary. Perform TEST VER-1. 2) If voltage does not change, condition required to set fault is not present at this time.
Page 221
NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION at beginning of article. For wiring diagrams, see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. 1) Using DRB-II, read Intake Air Temperature Sensor (IAT) voltage. If IAT voltage is less than .5 volt, go to step 4). If IAT voltage is more than .5 volt, wiggle wiring harness from IAT sensor to Powertrain Control Module (PCM) while observing DRB-II.
Page 222
Black/Red wire. Perform TEST VER-1. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-1. TEST FC-16A - THROTTLE POSITION SENSOR VOLTAGE HIGH NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION at beginning of article. For wiring diagrams, see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section.
Page 223
than .2 volt or if vehicle speed is more than 20 MPH, engine speed is more than 1500 RPM and vacuum is less than 2 in. Hg with TPS signal circuit (Orange/Dark Blue wire) less than .5 volt. Possible causes are: short to ground in TPS signal circuit (Orange/Dark Blue wire), TPS sensor failure or open TPS 5-volt supply circuit (Violet/White wire).
Page 224
connector using DRB-II. 8) If resistance is more than 10 ohms, but less than 75 ohms, go to step 10). If resistance is less than 10 ohms, repair IAC driver circuits No. 1 and 2 for shorting together. See appropriate PCM TERMINAL IDENTIFICATION table for wire color identification.
Page 225
INJECTOR #1 CONTROL CIRCUIT, go to step 6). 3) INJECTOR #1 CONTROL CIRCUIT fault sets if Powertrain Control Module (PCM) does not detect injector "turn off edge" when expected. Possible causes are: open or shorted injector ground circuit (White/Dark Blue wire), open injector power supply circuit (Dark Green/Orange wire on XJ and YJ bodies or Dark Green/Black wire on ZJ body), open injector, or failed driver in Powertrain Control Module (PCM).
Page 226
5) Start engine. Wiggle wiring harness from injector No. 2 to Powertrain Control Module (PCM). If engine misfires or stalls, repair wiring harness as necessary. Perform TEST VER-1. If engine does not misfire or stall, see INACTIVE FAULT CONDITION. Perform TEST VER-1. 6) Turn ignition off.
Page 227
Dark Green/Black wire on ZJ body. If voltage is less than 10 volts, repair open in Dark Green/Orange wire on XJ and YJ bodies or Dark Green/Black wire on ZJ body. Perform TEST VER-1. 8) If voltage is more than 10 volts, turn ignition off. Disconnect Powertrain Control Module (PCM) connector.
Page 228
connector terminal No. 13, injector driver circuit (Light Blue/Brown wire). If resistance is less than 5 ohms, repair short to ground in Light Blue/Brown wire. Perform TEST VER-1. If resistance is more than 5 ohms, replace PCM. Perform TEST VER-1. TEST FC-23A - INJECTOR #5 CONTROL CIRCUIT NOTE: For connector terminal identification, see CONNECTOR...
Page 229
see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. 1) Using DRB-II, erase fault messages. Attempt to start engine. If engine will not start, crank engine for at least 10 seconds. 2) Using DRB-II, read fault messages. If engine started, allow engine to idle for at least 20 seconds.
Page 230
2) Condition required to set fault is not present at this time. A/C CLUTCH RELAY CIRCUIT fault sets if A/C clutch relay control circuit(Dark Blue/Orange wire on XJ and YJ bodies or Dark Blue/Red wire on ZJ body) is not in its proper state when monitored by Powertrain Control Module (PCM).
Page 231
step. 3) Inspect all related wiring and connectors and repair as necessary. Perform TEST VER-1. If no problems were found with wiring and connectors, go to next step. 4) While still actuating radiator fan relay, wiggle wiring harness from radiator fan relay to Powertrain Control Module (PCM). Stop actuation of radiator fan relay.
Page 232
good ASD relay is clicking, replace original ASD relay. Perform TEST VER-1. If known good ASD relay is not clicking, remove known good ASD relay. 6) DRB-II should still be actuating ASD relay. Using DRB-II in voltmeter mode, check voltage on ASD relay connector, ignition feed circuit (Dark Blue wire on XJ body, White/Yellow wire on YJ body or Light Blue/Red wire on ZJ body).
Page 233
7) If resistance is more than 5 ohms, repair open in Dark Green/Orange wire on XJ and YJ bodies or Dark Green/Black wire on ZJ body. Perform TEST VER-1. If resistance is less than 5 ohms, reconnect PCM connector. Install a known good ASD relay. Attempt to start engine.
Page 234
6) Using DRB-II in voltmeter mode, check voltage of ignition feed circuit (Dark Blue/White wire). If voltage is less than 10 volts, repair open in Dark Blue/White wire. Perform TEST VER-1. If voltage is more than 10 volts, turn ignition off. Disconnect Powertrain Control Module (PCM) connector.
Page 236
2 kg/cm £ ). If fuel pressure increases, replace fuel pressure regulator. Perform TEST VER-1. If fuel pressure does not increase, replace fuel pump and sock assembly. Perform TEST VER-1. TEST NF-3B - CHECKING FUEL PRESSURE WARNING: High fuel pressure may be present in fuel lines. Open fuel system with caution.
Page 237
properly. Test is complete. TEST NF-6A - CHECKING MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR CALIBRATION 1) Turn engine off. Install vacuum "T" in MAP sensor vacuum hose. Install vacuum gauge. Start engine and let idle. If engine will not idle, maintain a constant RPM above idle. Using DRB-II, read MAP value.
Page 238
4) Turn engine off. Replace O2 sensor. Turn ignition on. Using DRB-II, reset adaptive fuel memory. Start engine. Allow engine to reach normal operating temperature. 5) Using DRB-II, read O2 sensor state. If O2 sensor state is switching, repair is complete. Perform TEST VER-1. If O2 sensor state is not switching, go to TEST NF-12A.
Page 240
in Black/Tan wire on XJ and ZJ bodies or Black wire on YJ body. Perform TEST VER-1. If resistance is less than 5 ohms, go to next step. 3) Using DRB-II, check resistance of PCM connector terminal No. 12, power ground circuit (Black/Tan wire on XJ and ZJ bodies or Black wire on YJ body).
Page 241
cap. Hold cable within 1/4" of ground. While cranking engine for 10 seconds, watch for spark. If good spark does not occur, go to next step. If good spark occurs, repair distributor cap, rotor or spark plug cables as necessary. Perform TEST VER-1. 4) Turn ignition off.
Page 242
ignition on. Using DRB-II, actuate fuel system. Read fuel pressure gauge reading. 6) If fuel pressure is more than 43 psi (3.0 kg/cm £ ), go to TEST NS-4B. If fuel pressure is not more than 43 psi (3.0 kg/cm £...
Page 243
5) Gently squeeze fuel return hose. Read fuel pressure gauge. Using DRB-II, stop fuel system actuator test. If pressure is more than 34 psi (2.3 kg/cm £ ), replace fuel pressure regulator. Perform TEST VER-1. If it is less than 34 psi (2.3 kg/cm £...
Page 244
jumper wire between fuel pump relay connector, output circuit (Dark Green/Orange wire on XJ body, Dark Green/Black wire on YJ body or Orange/Black wire on ZJ body) and ground. 6) Using DRB-II in ohmmeter mode, check resistance of fuel pump connector, output circuit (Dark Green/Black wire on XJ and YJ bodies or Orange/Dark Blue wire on ZJ body).
Page 245
check voltage on TPS connector, 5-volt supply circuit (Violet/White wire). If voltage is more than 4.4 volts, replace MAP sensor. Perform TEST VER-1. 6) If voltage is less than 4.4 volts, turn ignition off. Disconnect PCM connector. Using DRB-II in ohmmeter mode, check resistance of PCM connector terminal No.
Page 246
see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. 1) If ignition was not on when NO RESPONSE message was displayed, turn ignition on to get a response. If ignition was on when NO RESPONSE message was displayed, turn ignition off. 2) Disconnect DRB-II from engine diagnostic connector.
Page 247
TEST NS-7A - INSPECTING IDLE AIR CONTROL MOTOR OPERATION NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION at beginning of article. For wiring diagrams, see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. 1) Disconnect Idle Air Control (IAC) motor connector. Turn ignition on.
Page 248
TEST NS-7D - INSPECTING IDLE AIR CONTROL MOTOR OPERATION NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION at beginning of article. For wiring diagrams, see L - WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. 1) Turn ignition off. Disconnect Powertrain Control Module (PCM) connector.
Page 249
changed, repair is complete. 4) If engine starts and PCM was not changed, connect DRB-II to engine diagnostic connector and erase fault messages. Repair is complete. TEST VER-2 - VERIFICATION TEST VER-2 Inspect vehicle to ensure all engine components are connected.
H - TESTS W/O CODES 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. Trouble Shooting - No Codes Jeep; Cherokee, Grand Wagoneer, Grand Cherokee, Wrangler INTRODUCTION CAUTION: When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle.
Page 251
See appropriate F - BASIC TESTING article. ENGINE FAILS TO START, NO SPARK AT PLUGS Ensure distributor cap is not cracked or carbon-tracked. Check for defective rotor. Check for corroded wires and connections. See appropriate F - BASIC TESTING article. ENGINE BACKFIRES, FAILS TO START Ensure distributor cap is not cracked or carbon-tracked.
Page 252
Remove/apply vacuum source. Monitor circuit/component voltage or resistance while simulating intermittent. If engine is running, monitor for self-diagnostic codes. Use test results to identify a faulty component or circuit.
Page 253
I - SYSTEM/COMPONENT TESTS - 2.5L & 4.0L 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. 2.5L & 4.0L System & Component Testing Jeep; Cherokee, Grand Cherokee, Wrangler INTRODUCTION NOTE: For Grand Cherokee with 5.2L engine, see I - 5.2L SYS/COMP TESTS article in this section.
Page 254
section. 6) If voltage is present at supply wire, replace camshaft position sensor. If voltage is present at PCM pin No. 7, but not at supply wire, check continuity of supply wire between the distributor connector and the PCM. If no continuity exists, repair wiring harness as necessary.
Page 255
Grand Cherokee). 2) Ohmmeter should indicate an open circuit. Replace sensor if reading is not as specified. Also see appropriate crankshaft position sensor tests in G - 2.5L & 4.0L TESTS W/ CODES article in this section. Manifold Absolute Pressure (MAP) Sensor 1) Inspect MAP sensor vacuum hose connections at throttle body and sensor.
Page 256
1) Disconnect park/neutral switch. Ensure continuity exists between terminals "B" and "C" with transmission in Park or Neutral. See Fig. 1. 2) Ensure continuity exists between terminals "A" and "E" with transmission in Reverse. See Fig. 1. Ensure continuity exists between terminals "A"...
Page 257
this section. Park/Neutral Switch (32RH Auto. Trans.) 1) Disconnect park/neutral switch. Check continuity between switch center terminal and transmission case. Continuity should exist only when transmission is in Park or Neutral. 2) Shift transmission into Reverse. Check continuity between the 2 outside terminals on switch. Continuity should exist only when transmission is in Reverse.
Page 258
exists, replace security alarm module relay and retest. If continuity does not exist, repair open in wiring circuit as necessary and retest. 5) Check for battery voltage at security alarm module relay terminal No. 3. If battery voltage is not present, repair open in wiring circuit as necessary.
Page 259
lock position and then unlock. If power door locks do not operate properly, replace door lock switch(es), lock/unlock relay(s) or repair wiring harness as necessary. Retest system. 17) If power door locks operate properly, lock and unlock vehicle with keyless entry transmitter. If power door locks do not operate properly, replace keyless entry transmitter, receiver or repair wiring harness as necessary and retest system.
Fig. 2: Identifying Relay Terminals & Testing Relays (Typical) Courtesy of Chrysler Corp. FUEL SYSTEM...
Page 261
FUEL DELIVERY NOTE: Always relieve fuel pressure before disconnecting any fuel injection-related component. Also see appropriate fuel delivery system or fuel injector control circuit tests in G - 2.5L & 4.0L TESTS W/ CODES article in this section. Fuel System Pressure Release Procedure 1) Disconnect negative battery cable.
Page 262
connected to fuel pressure regulator. £ 3) If fuel pressure is not 8-10 psi (.56-.70 kg/cm ) higher with vacuum hose disconnected from fuel pressure regulator, inspect vacuum hose for blockage, leaks, kinks or other damage. If vacuum hose is okay, replace fuel pressure regulator. 4) If fuel pressure exceeds 45 psi (3.1 kg/cm £...
regulator. Replace fuel pressure regulator. Fuel Pump Capacity Test 1) Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE PROCEDURE heading above. Disconnect fuel supply line at fuel rail near fuel pressure regulator. Connect 3/8" fuel hose to disconnected fuel supply line. Insert other end of hose into approved gasoline container.
check IAC motor bore in throttle body and clean if necessary. Reinstall IAC motor and retest. 7) If throttle body is clear of obstructions, USE A Chrysler Corp. Diagnostic Readout Box II (DRB-II) tester and refer to appropriate IAC motor tests in G - 2.5L & 4.0L TESTS W/ CODES article in this section.
Page 268
Fig. 3: Wiring Diagram (4.0L - Grand Cherokee)
Page 269
Fig. 4: Wiring Diagram (5.2L - Grand Cherokee & Grand Wagoneer)
Page 270
M - VACUUM DIAGRAMS 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. Vacuum Diagrams Jeep; Cherokee, Grand Wagoneer, Grand Cherokee, Wrangler INTRODUCTION This article contains underhood views of vacuum hose routing. Use these vacuum diagrams during the visual inspection portion of F - BASIC TESTING article in the ENGINE PERFORMANCE Section.
Page 271
Fig. 2: Engine Vacuum Diagram (4.0L) Courtesy of Chrysler Corp. Fig. 3: Engine Vacuum Diagram (5.2L) Courtesy of Chrysler Corp.
N - REMOVE/INSTALL/OVERHAUL 1993 Jeep Cherokee 1993 ENGINE PERFORMANCE Chrysler Corp. Removal, Overhaul & Installation Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler INTRODUCTION Removal, overhaul and installation procedures are covered in this article. If component removal and installation is primarily an unbolt and bolt-on procedure, only a torque specification may be furnished.
seated on distributor. Replace "O" ring if cracked or nicked. Carefully engage distributor driven gear with camshaft drive gear so when distributor is installed properly, rotor aligns with reference mark. 2) Install hold-down clamp and bolt but do not tighten. Rotate distributor housing until rotor is aligned with CYL.
Page 274
WARNING: ALWAYS relieve fuel pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components. 1) Disconnect negative battery cable. Loosen fuel filler cap to release tank pressure. Remove protective cap from pressure test port on fuel rail.
Page 275
NOTE: Fuel tank removal is not necessary when removing fuel pump module on Cherokee and Grand Cherokee. Removal & Installation (Cherokee) 1) Relieve fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE. Remove fuel tank filler cap. Drain fuel tank until fuel level is below 1/4 full. Raise and support vehicle. Disconnect fuel gauge sending unit connector.
straps securing connector harness to fuel supply and return tubes. Disconnect fuel tank vent hose from vent tube. 3) Remove fuel tank shield and skid plate as single assembly. Support fuel tank with floor jack, and remove support strap nuts. Lower fuel tank and remove.
P - EGR FUNCTION TESTING 1993 Jeep Cherokee 1990-95 ENGINE PERFORMANCE Jeep EGR Function Testing All Models EGR VALVE PORTED EGR SYSTEM 1) Check vacuum hoses for correct routing. Warm engine to normal operating temperature. Set engine speed to fast idle (or high enough to obtain 5 in Hg at EGR valve).
FUSES & CIRCUIT BREAKERS 1993 Jeep Cherokee Fuses & Circuit Breakers 1993-95 Jeep Jeep; Cherokee IDENTIFICATION FUSES & CIRCUIT BREAKERS The fuse block is to the left of the steering column, under the instrument panel. Fig. 1: Fuse Panel Identification (1993-95) Courtesy of Chrysler Corp.
Page 279
1 - 25 Amp (Natural) Rear Window Wiper, Washer. 2 - 15 Amp (Lt. Blue) Radio, Cigar Lighter, Dome Lamp (1993). 3 - Not Used Not Used. 4 - 15 Amp (Lt. Blue) Flash to Pass. 5 - 25 Amp (Natural) (1992) Blower Motor.
Page 280
RELAY PANEL IDENTIFICATION (1993-95 MODELS) The relay panel is to the right of the steering column, under the instrument panel. Fig. 2: Relay Block Identification (1993-95 Models) Courtesy of Chrysler Corp. RELAY IDENTIFICATION (PASSENGER COPMPARTMENT)
Page 281
1 - Illuminated Entry Relay (1993-94); Not Used (1995) No additional definition. 2 - Horn Relay (1993-94); Dual Flasher Relay (1995) No additional definition. 3 - Rear Window Defogger Relay No additional definition. 4 - Not Used No additional definition. 5 - Not Used (1993-94);...
Page 283
SUPPLEMENTAL RESTRAINT (AIR BAG SYSTEM) (IF EQUIPPED) WARNING: The Diagnostic Energy Reserve Module (DERM) can maintain enough voltage to cause a deployment of the Inflator Module for up to 10 minutes after the Ignition Switch is turned off and the battery is disconnected. Many of the service procedures require disconnection of the Inflator Module to avoid an accidental deployment.
Page 285
Graphic No. 2 In power distribution center. ABS System Relay Graphic No. 1 In power distribution center.
Page 286
Graphic No. 2 In power distribution center. A/C Clutch Relay In power distribution center, on right fender apron.
Page 287
A/C-Heater Relays Behind right side of dash, on evaporator housing. Auto Shutdown Relay...
Page 288
Graphic No. 1 In power distribution center. Graphic No. 2 In power distribution center. Auxiliary Cooling Fan Relay In power distribution center.
Page 289
Ballast Resistor By-Pass Relay 4-Cylinder On right fender apron, near power distribution center. Graphic No. 2 On right fender apron, near power distribution center. Blower Relays...
Page 290
High Speed Behind right side of dash, on evaporator housing. Medium Speed Behind right side of dash, on evaporator housing.
Page 291
Cooling Fan Relay Graphic No. 1 In power distribution center, on right fender apron. Graphic No. 2 In power distribution center, on right fender apron.
Page 292
Foglight Relay Behind left head light, on wheelwell. Fuel Pump Relay Graphic No. 1 In power distribution center, on right fender apron.
Page 293
Graphic No. 2 In power distribution center, on right fender apron. Hazard Flasher Relay In fuse block. Horn Relay On relay center. Power Antenna Relay Under right side of dash,...
Page 294
behind glove box. Radio/Clock Illumination Relay On relay center. Rear Window Defogger Relay On relay center. Starter Relay Graphic No. 1 In power distribution center, on right fender apron.
Page 295
Graphic No. 2 In power distribution center, on right fender apron. Trailer Towing Relays Brake Lights Behind left rear quarter trim panel. Left & Right Turn Signals Behind left rear quarter trim panel.
Page 300
Powertrain Control Module (PCM) 4-Cylinder On left front fender apron, behind air cleaner. Security System Module On bracket, left side of A/C-heater housing.
Page 302
Idle Air Control Motor On throttle body assembly. Washer Motor Front On bottom of washer fluid reservoir, in engine compartment. Rear On bottom of washer fluid reservoir, in engine compartment. Windshield Wiper Motor Behind left side of firewall, under cowl trim panel. SENDING UNITS &...
Page 303
Camshaft Position Sensor Inside ignition distributor assembly. Coolant Temperature Sensor For Engine Control...
Page 304
4-Cylinder On thermostat housing. 6-Cylinder On thermostat housing. For Gauges...
Page 305
4-Cylinder At left rear of cylinder head. 6-Cylinder At left rear of cylinder head.
Page 306
Crankshaft Position Sensor On left side of transmission bellhousing. Fuel Gauge Sending Unit In fuel tank, part of fuel pump assembly. Intake Air Temperature Sensor (IAT)
Page 307
4-Cylinder On intake air plenum, near throttle body. 6-Cylinder On intake air plenum, near throttle body. Manifold Absolute Pressure Sensor (MAP) On center of firewall.
Page 308
Oil Pressure Sending Unit (4-Cylinder) On right side of engine block. (6-Cylinder) On right side of engine block.
Page 309
Overhead Console Ambient Temperature Sensor On right side of lower radiator support. Throttle Position Sensor (TPS) 4-Cylinder On throttle body assembly.
Page 310
6-Cylinder On throttle body assembly. Vehicle Speed Sensor On transmission extension housing. SOLENOIDS & SOLENOID VALVES...
Page 314
(6-Cylinder) On brake pressure differential valve, below master cylinder. Parking Brake Switch Under center console, at base of parking brake lever. Power Steering Pressure Switch...
Page 315
4-Cyl Near power steering pump, on high pressure hose. 6-Cyl. Near power steering pump, on high pressure hose. Seat Belt Switch In driver’s seat belt buckle.
ELECTROSTATIC DISCHARGE WARNING - BASIC INFORMATION 1993 Jeep Cherokee GENERAL INFORMATION Electrostatic Discharge (ESD) Warning - Basic Information All Makes amd Models * PLEASE READ THIS FIRST * NOTE: This article is intended for general information purposes only. INTRODUCTION All Electrostatic Discharge (ESD) sensitive components contain solid state circuits (transistors, diodes, semiconductors) that may become damaged when contacted with an electrostatic charge.
Page 321
When handling an electronic part that is ESD sensitive, the technician should follow these guidelines to reduce any possible electrostatic charge build-up on the technician’s body and the electronic part. 1) Always touch a known good ground source before handling the part.
Page 322
HOW TO USE SYSTEM WIRING DIAGRAMS 1993 Jeep Cherokee GENERAL INFORMATION Using Wiring Diagrams All Models INTRODUCTION This cd obtains wiring diagrams and technical service bulletins, containing wiring diagram changes from the domestic and import manufacturers. These are checked for accuracy and are all redrawn into a consistent format for easy use.
Page 323
article in GENERAL INFORMATION. IDENTIFYING WIRING DIAGRAM SYMBOLS NOTE: Standard wiring symbol are used in these diagrams. The illustration below will help clarify any symbols that are not easily understood at a glance. Most components are labeled "Motor", "Switch" or "Relay" in addition to being drawn with the standard symbol.
Page 324
WIRING DIAGRAM COMPONENT LOCATIONS When trying to locate a component in a wiring diagram and you don’t know the specific system where it is located, use this handy component locator to find the system wiring diagram in which the component is located. Then, go to that system and locate the component within the wiring diagram.
Page 325
Brake On/Off (BOO) Switch ....Cruise Control Systems Engine Performance Shift Interlock Systems Buzzer Module ........Warning Systems Camshaft Position (CMP) Sensor ....Engine Performance Central Control Module ......Anti-Theft System Clockspring ....... Air Bag Restraint System Cruise Control Systems Steering Column Switches Clutch Pedal Position Switch ......
Page 326
Starters Generator ........Generators & Regulators Engine Performance Power Distribution Generic Electronic Module (GEM) ....Body Control Modules Electronic Suspension Glow Plug Relay ......... Engine Performance Glow Plugs ........Engine Performance Grounds ........Ground Distribution Headlight Door Module ......Headlight Doors Headlight Relay ........
Page 327
Parking Brake Switch ...... Analog Instrument Panels Park Lights ........Exterior Lights Park/Neutral Position Switch ......Starters Engine Performance Anti-Theft System Body Control Module Perimeter Lighting Control Relay ....Exterior Lights Power Amplifier ........Power Antennas Power Antenna Module ........ Power Antennas Power Antenna Motor .........
Page 328
Torque Converter Clutch Solenoid/Switch ..Engine Performance Traction Control Switch ......Anti-Lock Brakes Trailer Tow Connector ......Exterior Lights Trailer Tow Relay ........Exterior Lights Transmission/Transaxle ......Engine Performance Transmission Control Module (TCM) ....Engine Performance Starters Transmission Range Sensor .........
WIRING DIAGRAM SYMBOLS 1993 Jeep Cherokee WIRING DIAGRAMS How To Use The Wiring Diagrams WIRING DIAGRAMS INTRODUCTION The wiring diagrams and technical service bulletins, containing wiring diagram changes, are obtained from the domestic and import manufacturers. These are checked for accuracy and are all redrawn into a consistent format for easy use.
Page 330
Fig. 1: Identifying Tie-Off Symbols 4) If the wires are not drawn all the way to another component (across several pages), a reference will tell you their final destination. 5) Again, use the legend on the first page of the wiring diagram to determine the grid number and letter of the referenced component.
Page 366
WAVEFORMS - INJECTOR PATTERN TUTORIAL 1993 Jeep Cherokee GENERAL INFORMATION Waveforms - Injector Pattern Tutorial * PLEASE READ THIS FIRST * NOTE: This article is intended for general information purposes only. This information may not apply to all makes and models.
Page 367
The noid light is an excellent "quick and dirty" tool. It can usually be hooked to a fuel injector harness fast and the flashing light is easy to understand. It is a dependable way to identify a no- pulse situation. However, a noid light can be very deceptive in two cases: If the wrong one is used for the circuit being tested.
Page 368
the types of injector circuits that your noid lights are designed for. There are three. They are: Systems with a voltage controlled injector driver. Another way to say it: The noid light is designed for a circuit with a "high" resistance injector (generally 12 ohms or above). Systems with a current controlled injector driver.
Page 369
full load. The Kent-Moore J-39021 is such a tool, though there are others. The Kent-Moore costs around $240 at the time of this writing and works on many different manufacturer’s systems. The second method is to use a lab scope. Remember, a lab scope allows you to see the regular operation of a circuit in real time.
Page 370
but it cannot figure out the throttling action. In other words, it cannot distinguish the throttling from an open circuit (de-energized) condition. Yet current controlled injectors will still yield a millisecond on-time reading on these DVOMs. You will find it is also always the same, regardless of the operating conditions.
Page 371
severe weakness that we will look at later). If an injector has a fault where it occasionally skips a pulse, the meter registers it and the reading changes accordingly. Let’s go back to figuring out dwell/duty readings by using injector on-time specification. This is not generally practical, but we will cover it for completeness.
Page 372
3800 engines were suffering from exactly this. The point is that a lack of detail could cause misdiagnosis. As you might have guessed, a lab scope would not miss this. RELATIONSHIP BETWEEN DWELL & DUTY CYCLE READINGS TABLE ( 1) ¡...
Page 373
times by increasing injector pulse width accordingly. NOTE: Never apply battery voltage directly across a low resistance injector. This will cause injector damage from solenoid coil overheating. Fig. 1: Injector Driver Types - Current and Voltage CURRENT CONTROLLED CIRCUIT ("PEAK & HOLD") The current controlled driver inside the computer is more complex than a voltage controlled driver because as the name implies, it has to limit current flow in addition to its ON-OFF switching...
Page 374
Only a handful of systems use the drivers on the power side of the circuit. Some examples of the latter are the 1970’s Cadillac EFI system, early Jeep 4.0 EFI (Renix system), and Chrysler 1984-87 TBI.
Page 375
will need to shift your Lab Scope to five volts per division. You will find that some systems have slight voltage fluctuations here. This can occur if the injector feed wire is also used to power up other cycling components, like the ignition coil(s). Slight voltage fluctuations are normal and are no reason for concern.
Page 376
the iron core here. This pintle hump at Point "E" should occur near the end of the downward slope, and not afterwards. If it does occur after the slope has ended and the voltage has stabilized, it is because the pintle is slightly sticking because of a faulty injector If you see more than one hump it is because of a distorted pintle or seat.
Page 377
drivers. They typically require injector circuits with a total leg resistance with less than 12 ohm. NOTE: This example is based on a constant power/switched ground circuit. See Fig. 3 for pattern that the following text describes. Point "A" is where system voltage is supplied to the injector.
Page 378
a good injector will be 60 or more volts. At Point "E", notice that the trace is now just a few volts below system voltage and the injector is in the current limiting, or the "Hold" part of the pattern. This line will either remain flat and stable as shown here, or will cycle up and down rapidly.
Page 379
CURRENT WAVEFORM SAMPLES EXAMPLE #1 - VOLTAGE CONTROLLED DRIVER The waveform pattern shown in Fig. 4 indicate a normal current waveform from a Ford 3.0L V6 VIN [U] engine. This voltage controlled type circuit pulses the injectors in groups of three injectors.
Page 380
Fig. 5: Injector Bank w/Excessive Current Flow - Current Pattern Fig. 6: Single Injector w/Normal Current Flow - Current Pattern Fig. 7: Single Injector w/Excessive Current Flow - Current Pattern...
Page 381
EXAMPLE #2 - VOLTAGE CONTROLLED DRIVER This time we will look at a GM 3.1L V6 VIN [T]. Fig. 8 shows the 1, 3, 5 (odd) injector bank with the current waveform indicating about a 2.6 amp draw at idle. This pattern, taken from a known good vehicle, correctly stays at or below the maximum 2.6 amps current range.
Page 382
Fig. 9: Injector Even Bank w/Normal Current Flow - Current Pattern EXAMPLE #3 - VOLTAGE CONTROLLED DRIVER Example #3 is of a Ford 5.0L V8 SEFI. Fig. 10 shows a waveform of an individual injector at idle with the Lab Scope set on 200 milliamps per division.
Page 383
Fig. 11: Single Injector w/Excessive Current Flow - Current Pattern EXAMPLE #4 - CURRENT CONTROLLED DRIVER Example #4 is of a Ford 4.6L SEFI VIN [W]. See Fig. 12 for the known-good waveform pattern. This Ford system is different from the one above in EXAMPLE #3 as it peaks at 900 milliamps and the actual opening of the injector (set point) is just below 600 milliamps.
Page 384
PFI VIN [3]. It is a perfect example of the peak and hold theory. The waveform shows a 1-amp per division current flow, ramping to 4 amps and then decreasing to 1-amp to hold the injector open. Fig. 13: Injector Bank w/Normal Current Flow - Current Pattern EXAMPLE #6 - CURRENT CONTROLLED DRIVER This next known-good waveform is from a Ford 5.0L V8 CFI VIN [F].
Page 385
that it shows a faulty injector. See Fig. 16. Notice that the current went to almost 5 amps and stayed at 1 amp during the hold pattern. Excessive amounts of current flow from bad injectors are a common source of intermittent computer shutdown. Using a current waveform pattern is the most accurate method of pinpointing this problem.
Page 386
Fig. 17: Single Injector w/Normal Current Flow - Current Pattern VOLTAGE WAVEFORM SAMPLES EXAMPLE #1 - VOLTAGE CONTROLLED DRIVER These two known-good waveform patterns are from a Ford 4.6L V8 VIN [W]. Fig. 18 illustrates the 64 volt inductive kick on this engine, indicating no clamping is occurring.
Page 387
Fig. 18: Injector Bank - Known Good - Voltage Pattern...
Page 388
Fig. 19: Injector Bank - Known Good - Voltage Pattern EXAMPLE #2 - VOLTAGE CONTROLLED DRIVER The known-good waveform pattern in Fig. 20 is from a GM 3.8L V6 PFI VIN [3]. It was taken during hot idle, closed loop and no load.
Page 389
Fig. 20: Injector Bank - Known Good - Voltage Pattern EXAMPLE #3 - VOLTAGE CONTROLLED DRIVER This known-good waveform pattern, Fig. 21, is from a GM 5.0L V8 TPI VIN [F]. It was taken during hot idle, closed loop and no load.
Page 390
Fig. 21: Injector Bank - Known Good - Voltage Pattern EXAMPLE #4 - CURRENT CONTROLLED DRIVER From 1984 to 1987, Chrysler used this type injector drive on their TBI-equipped engines. See Fig. 22 for a known-good pattern. Instead of the ground side controlling the injector, Chrysler permanently grounds out the injector and switches the power feed side.
Page 391
Fig. 22: Single Injector - Known Good - Voltage Pattern EXAMPLE #5 - CURRENT CONTROLLED DRIVER These two known-good waveform patterns are from a Chrysler 3. 0L V6 VIN [3]. The first waveform, Fig. 23, is a dual trace pattern that illustrates how Chrysler uses the rising edge of the engine speed signal to trigger the injectors.
Page 392
Fig. 23: Injector Bank - Known Good - Voltage Pattern...
Page 393
Fig. 24: Injector Bank - Known Good - Voltage Pattern EXAMPLE #6 - CURRENT CONTROLLED DRIVER This known-good pattern from a Ford 3.0L V6 PFI VIN [U] illustrates that a zener diode inside the computer is used to clamp the injector’s inductive kick to 35-volts on this system. See Fig. 25.
Page 394
Fig. 25: Injector Bank - Known Good - Voltage Pattern EXAMPLE #7 - CURRENT CONTROLLED DRIVER This known-good waveform from a Ford 5.0L V8 CFI VIN [F] was taken during hot idle, closed loop, and no load. See Fig. 26.
Page 395
Fig. 26: Single Injector - Known Good - Voltage Pattern EXAMPLE #8 - CURRENT CONTROLLED DRIVER These two known-good waveform patterns are from a GM 2.0L In- Line 4 VIN [1]. Fig. 27 illustrates the 78 volt inductive spike that indicates a zener diode is not used.
Page 396
Fig. 27: Single Injector - Known Good - Voltage Pattern...
Page 397
Fig. 28: Single Injector - Known Good - Voltage Pattern...
Page 398
CLUTCH 1993 Jeep Cherokee 1993 Clutch Hydraulic Cherokee, Grand Cherokee, Wrangler DESCRIPTION The clutch assembly consists of a single dry-disc driven plate and a one-piece diaphragm spring-type clutch cover. The clutch is actuated through a hydraulic master cylinder and a slave cylinder.
Mark drive shaft yokes and transfer case yokes for reassembly reference. Disconnect drive shafts. 3) Support transfer case with jack and lower (NOT MORE than 3 inches). Reaching up and around transmission case, move boot upward to access shift lever retainer. NOTE: DO NOT remove shift lever from floor pan boot.
CLUTCH MASTER CYLINDER Removal Disconnect hydraulic line at master cylinder. On Grand Cherokee, disconnect hydraulic line from remote reservoir to master cylinder. Plug all hydraulic lines and openings. On all models, remove cotter pin or spring clip holding push rod on clutch pedal. Slide push rod off pedal pivot.
prevent fluid loss and contamination. Remove slave cylinder mounting bolts. Remove slave cylinder. To install, reverse removal procedure. PILOT BEARING Removal & Installation Remove clutch assembly. Using slide hammer and internal puller, remove pilot bearing. To install, lubricate pilot bearing with wheel bearing grease.
G - AUTO TRANS DIAGNOSIS - 4.0L MODELS W/AW4 1993 Jeep Cherokee AUTOMATIC TRANSMISSIONS Aisin Warner 4 Electronic Diagnosis 1993-94 Cherokee APPLICATION NOTE: Transmission may also be referred to as AW-4. APPLICATION ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡...
Page 403
NOTE: Diagnostic trouble code may be referred to as fault code. Diagnostic trouble codes can be retrieved using a Diagnostic Readout Box-II (DRB-II). After repairing an electrical system problem, stored diagnostic trouble code must be cleared from TCM memory. The TCM is located behind right side of instrument panel on Cherokee.
Page 405
Brake switch is an input device mounted above the brake pedal. When brake pedal is operated, brake switch delivers an input signal to the TCM. The TCM uses input signal for controlling No. 3 valve body solenoid for torque converter lock-up. NEUTRAL SAFETY SWITCH NOTE: Neutral safety switch may be referred to as park/neutral...
Page 406
using DRB-II, you must first enter AW4 MENU and then retrieve diagnostic trouble codes. NOTE: Ensure TEST 1A - VERIFICATION OF COMPLAINT is performed when trouble shooting the vehicle. This test checks for diagnostic trouble codes with vehicle stationary and during road test.
Page 407
KEYPAD TEST FAILURE LOW BATTERY RAM TEST FAILURE 3) If no error messages appear, display will read as follows after a few seconds: 1) VEHICLES TESTED, 2) HOW TO USE, 3) CONFIGURE and 4) SELECT SYSTEM. 4) Select 4) SELECT SYSTEM to enter diagnostic system. Once in SELECT SYSTEM, select 2) TRANSMISSION to enter transmission.
CAUTION: DO NOT disconnect battery, as data stored in other vehicle control modules will be lost. 2) The TCM is located behind right side of instrument panel on Cherokee. See Fig. 1. DRB-II OPERATING MODES NOTE: The DRB-II can be operated in several different modes to perform various tests.
requested action is seen by the TCM. If technician is requested to perform a particular operation and TCM does not acknowledge the action, press ENTER key to continue testing. 6) The TCM will instruct technician to accelerate vehicle at light throttle to ensure transmission shifts through all gears, indicating proper valve body solenoid operation.
1) If KEYPAD TEST FAILURE message is displayed, disconnect DRB-II from transmission diagnostic connector. DO NOT touch keys on DRB-II keypad. Reconnect DRB-II to transmission diagnostic connector and note display. 2) If KEYPAD TEST FAILURE message is not displayed, proceed with diagnostics.
Page 412
Fig. 5: Identifying TPS Electrical Connector Courtesy of Chrysler Corp. VALVE BODY SOLENOID TEST With oil pan removed, disconnect electrical connector from valve body solenoid. Using ohmmeter, check resistance between valve body solenoid electrical terminal and solenoid mounting bracket. Replace valve body solenoid if resistance is not 11-15 ohms. TROUBLE SHOOTING CHARTS &...
Page 413
Fig. 6: TCM Connector Terminals I.D., Circuits & Functions Courtesy of Chrysler Corp. TEST 1A - VERIFICATION OF COMPLAINT NOTE: ALWAYS start diagnosis with the most recent code. 1) Begin your testing of the transmission with a thorough visual inspection. 2) Connect the DRB-II to the transmission diagnostic...
Page 414
connector. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF- DIAGNOSTIC SYSTEM for diagnostic connector location. CAUTION: If the vehicle is in 3rd or OD position and feels like it is stuck in 3rd or jumping from 2-1 or 3-1, perform TEST 10A - TESTING FOR INTERMITTENT SPEED SENSORS . 3) With the DRB-II, perform SYSTEM TEST.
Page 415
transmission. It must be performed after finding no faults using the DRB-II, and after a vehicle repair has been made. 1) Turn ignition key to "OFF". 2) Hold the MODE key and press the ATM key on the DRB-II at the same time to restart the DRB-II.
Page 416
Fig. 8: Test 3A - View of 7-Way Connector (Cherokee) TEST 4A - CODE 700 - S1 SOLENOID CIRCUIT...
Page 417
Fig. 9: Test 4A - Code 700, Flow Chart (1 of 2)
Page 456
Fig. 79: Test 6D - Code 703, Flow Chart (3 of 3)
Page 457
Fig. 80: Test 6D - Gear Select Switch Schematic (Cherokee) Fig. 81: Test 6D - Code 703, Location of Gear Select Switch Fig. 82: Test 6D - 8-Way Black Connector Cavity "A" (Cherokee)
Page 458
Fig. 83: Test 6D - 8-Way Black Connector Cavity "G" (Cherokee)
Page 459
Fig. 84: Test 6D - Code 703, TCU 32-Way Connector (Cavity 9) TEST 6E - CODE 703 - GEAR SELECT SWITCH CIRCUIT NOTE: Perform TEST 6D - CODE 703 - GEAR SELECT SWITCH CIRCUIT before proceeding. Fig. 85: Test 6E - Code 703, Flow Chart...
Page 460
Fig. 86: Test 6E - Gear Select Switch Schematic (Cherokee) Fig. 87: Test 6E - Code 703, Location of Gear Select Switch Fig. 88: Test 6E - 8-Way Black Connector Cavity "A" (Cherokee)
Page 461
Fig. 89: Test 6E - 8-Way Black Connector Cavity "H" (Cherokee) Fig. 90: Test 6E - TCU 32-Way Connector (Cavity 8) TEST 7A - CODE 705 - TPS CIRCUIT NOTE: Perform TEST 1A - VERIFICATION OF COMPLAINT before proceeding. NOTE: On Cherokee, engine diagnostic connector is located at left side of engine compartment, near engine controller.
Page 462
Fig. 91: Test 7A - Code 705, Flow Chart (1 of 2)
Page 464
Fig. 94: Test 7A - Code 705, Flow Chart (2 of 2)
Page 465
Fig. 95: Test 7A - Code 705, Schematic Fig. 96: Test 7A - Location of Throttle Position Sensor (TPS)
Page 466
Fig. 97: Test 7A - Code 705, View of TPS Connector Fig. 98: Test 7A - Location of Engine Control Connector (Cherokee)
Page 467
Fig. 99: Test 7A - View of Engine Control Connector (Cavity 22) TEST 8A - CODE 706 - BRAKE SWITCH CIRCUIT NOTE: Perform TEST 1A - VERIFICATION OF COMPLAINT before proceeding.
Page 469
Fig. 101: Test 8A - Code 706, Schematic (Cherokee) Fig. 102: Test 8A - TCU 32-Way Connector (Cavity 10, Cherokee) Fig. 103: Test 8A - Location of Brake Switch Connector...
Page 470
Fig. 104: Test 8A - Code 706, Flow Chart Fig. 105: Test 8A - Code 706, Schematic (Cherokee)
Page 471
Fig. 106: Test 8A - View of Engine Controller Connector (Cavity 29) Fig. 107: Test 8A - TCU 32-Way Connector (Cavity 10, Cherokee) Fig. 108: Test 8A - Location of Brake Switch Connector...
Page 472
Fig. 109: Test 8A - View of Brake Switch Connector (Cavity 3) Fig. 110: Test 8A - View of Brake Switch Connector (Cavity 6) TEST 8B - CODE 706 - BRAKE SWITCH CIRCUIT NOTE: Perform TEST 8A - CODE 706 - BRAKE SWITCH CIRCUIT before proceeding.
Page 473
Fig. 111: Test 8B - Code 706, Flow Chart Fig. 112: Test 8B - Code 706, Schematic (Cherokee)
Page 474
Fig. 113: Test 7A - Location of Engine Control Connector (Cherokee) Fig. 114: Test 8B - TCU 32-Way Connector (Cavity 10, Cherokee) TEST 9A - WRONG TCU NOTE: Perform TEST 1A - VERIFICATION OF COMPLAINT before proceeding. NOTE: The AW-4 is used only on 4.0L. In earlier years, it was...
Page 475
The DRB-II has determined that the wrong Transmission Control Unit (TCU) has been installed in the vehicle. There are two transmission control units available for the Jeep AW4 transmission. One is for the 4-cylinder 2.5L engine and the other is for the 6- cylinder 4.0L engine.
Page 476
Fig. 117: Test 10A - Location of Transmission Connectors Fig. 118: Test 10A - View of 7-Way Connector (Cherokee)
Fig. 125: TCM Connector Terminals I.D., Circuits & Functions Courtesy of Chrysler Corp. REMOVAL & INSTALLATION BRAKE SWITCH R & I Removal Remove lower steering column cover or trim panels for access to brake switch (if necessary). Disconnect brake switch electrical connector.
Page 482
Installation 1) Install brake switch in retainer. Reconnect brake switch electrical connector. 2) To check brake switch adjustment, slightly depress brake pedal and note operation of brake switch plunger. Brake switch plunger should fully extend when brake pedal free play is taken up and brake application begins.
Page 483
Removal & Installation 1) Disconnect electrical connector at speed sensor located on adapter housing or extension housing. Remove bolt and speed sensor. Remove "O" ring from speed sensor. 2) To install, reverse removal procedure using NEW "O" ring. Tighten bolt to specification. See TORQUE SPECIFICATIONS. THROTTLE POSITION SENSOR (TPS) R &...
Page 484
shaft on other side of TPS socket tangs. Fig. 128: Installing Throttle Position Sensor (TPS) Courtesy of Chrysler Corp. TRANSMISSION CONTROL MODULE (TCM) R & I Removal & Installation (Cherokee) Ensure ignition is off. Disconnect electrical connector from TCM, located behind right side of instrument panel. See Fig. 129. Remove fastener and TCM from instrument panel.
Removal 1) Raise and support vehicle. Remove drain plug and drain transmission fluid. Remove bolts and oil pan. Remove bolts, oil screen and gasket. 2) Disconnect electrical connectors from valve body solenoid. Mark electrical connector location for reassembly reference if more than one valve body solenoid is being removed.
AUTO TRANS DIAGNOSIS - AW4 1993 Jeep Cherokee AUTOMATIC TRANSMISSIONS Aisin Warner 4 Electronic Diagnosis APPLICATION NOTE: Transmission may also be referred to as AW-4. TRANSMISSION APPLICATION ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡...
Page 487
system will store a diagnostic trouble code in the TCM memory if certain electronic problems exist. If electronic problem goes away, diagnostic trouble code will be erased from TCM memory after ignition has been cycled approximately 75 times. NOTE: Diagnostic trouble code may be referred to as fault code. Diagnostic trouble codes can be retrieved using a Diagnostic Readout Box-II (DRB-II).
Brake switch is an input device mounted above the brake pedal. When brake pedal is operated, brake switch delivers an input signal to the TCM. The TCM uses input signal for controlling No. 3 valve body solenoid for torque converter lock-up. NEUTRAL SAFETY SWITCH NOTE: Neutral safety switch may be referred to as park/neutral...
Page 490
DRB-II scan tool. When retrieving diagnostic trouble codes using DRB-II, you must first enter AW4 MENU and then retrieve diagnostic trouble codes. NOTE: Ensure TEST 1A - VERIFICATION OF THE COMPLAINT is performed when trouble shooting the vehicle. This test checks for diagnostic trouble codes with vehicle stationary and during road test.
Page 491
* CARTRIDGE ERROR * HIGH BATTERY * KEYPAD TEST FAILURE * LOW BATTERY * RAM TEST FAILURE 3) If no error messages appear, display will read as follows after a few seconds: 1) VEHICLES TESTED, 2) HOW TO USE, 3) CONFIGURE and 4) SELECT SYSTEM.
Page 492
1) Once all diagnostic trouble codes have been obtained, diagnostic trouble code(s) can be erased from TCM memory by disconnecting electrical connector from TCM for at least 15 seconds. CAUTION: DO NOT disconnect battery, as data stored in other vehicle control modules will be lost.
Page 493
how fast accelerator is depressed. 5) After throttle position is checked, technician will be instructed to drive the vehicle. The DRB-II will indicate if a requested action is seen by the TCM. If technician is requested to perform a particular operation and TCM does not acknowledge the action, press ENTER key to continue testing.
Page 494
volts, check charging system. KEYPAD TEST FAILURE 1) If KEYPAD TEST FAILURE message is displayed, disconnect DRB-II from transmission diagnostic connector. DO NOT touch keys on DRB-II keypad. Reconnect DRB-II to transmission diagnostic connector and note display. 2) If KEYPAD TEST FAILURE message is not displayed, proceed with diagnostics.
Page 496
Fig. 5: Identifying TPS Electrical Connector Courtesy of Chrysler Corp. VALVE BODY SOLENOID With oil pan removed, disconnect electrical connector from valve body solenoid. Using ohmmeter, check resistance between valve body solenoid electrical terminal and solenoid mounting bracket. Replace valve body solenoid if resistance is not 11-15 ohms. TROUBLE SHOOTING CHARTS &...
Page 497
park/neutral or gear select switch. Fig. 6: TCM Connector Terminals I.D., Circuits & Functions Courtesy of Chrysler Corp. TEST 1A - VERIFICATION OF THE COMPLAINT NOTE: ALWAYS start diagnosis with the most recent code. 1) Begin your testing of the transmission with a thorough visual inspection.
Page 498
2) Connect the DRB-II to the transmission diagnostic connector. See RETRIEVING FAULT CODES under SELF-DIAGNOSTIC SYSTEM for diagnostic connector location. CAUTION: If the vehicle is in 3rd or OD position and feels like it is stuck in 3rd or jumping from 2-1 or 3-1, perform TEST 10A - TESTING FOR INTERMITTENT SPEED SENSOR test below.
Page 499
This test verifies the correct operation of the AW4 transmission. It must be performed after finding no faults using the DRB-II, and after a vehicle repair has been made. 1) Turn ignition key to "OFF". 2) Hold the MODE key and press the ATM key on the DRB-II at the same time to restart the DRB-II.
Page 500
Fig. 8: Test 3A - View of 7-Way Connector (Cherokee) TEST 4A - CODE 700 - S1 SOLENOID CIRCUIT...
Page 501
Fig. 9: Test 4A - Code 700, Flow Chart (1 of 2)
Page 520
Fig. 39: Test 4C - Code 700, TCU 32-Way Connector (Cavity 14) Fig. 40: Test 4C - Code 700, Location of Solenoids...
Page 521
Fig. 41: Test 4C - Code 700, Solenoid No. 1 Wire (Cavity "E") Fig. 42: Test 4C - Code 700, Testing S3 Control Wire...
Page 522
TEST 5A - CODE 702 - SPEED SENSOR CIRCUIT NOTE: Perform TEST 1A - VERIFICATION OF THE COMPLAINT before proceeding. Fig. 43: Test 5A - Code 702, Flow Chart (1 of 2)
Page 540
Fig. 79: Test 6D - Code 703, Flow Chart (3 of 3)
Page 541
Fig. 80: Test 6D - Gear Select Switch Schematic (Cherokee) Fig. 81: Test 6D - Code 703, Location of Gear Select Switch Fig. 82: Test 6D - 8-Way Black Connector Cavity "A" (Cherokee)
Page 542
Fig. 83: Test 6D - 8-Way Black Connector Cavity "G" (Cherokee)
Page 543
Fig. 84: Test 6D - Code 703, TCU 32-Way Connector (Cavity 9) TEST 6E - CODE 703 - GEAR SELECT SWITCH CIRCUIT NOTE: Perform TEST 6D - CODE 703 - GEAR SELECT SWITCH CIRCUIT before proceeding. Fig. 85: Test 6E - Code 703, Flow Chart...
Page 544
Fig. 86: Test 6E - Gear Select Switch Schematic (Cherokee) Fig. 87: Test 6E - Code 703, Location of Gear Select Switch Fig. 88: Test 6E - 8-Way Black Connector Cavity "A" (Cherokee)
Page 545
Fig. 89: Test 6E - 8-Way Black Connector Cavity "H" (Cherokee) Fig. 90: Test 6E - TCU 32-Way Connector (Cavity 8) TEST 7A - CODE 705 - TPS CIRCUIT NOTE: Perform TEST 1A - VERIFICATION OF THE COMPLAINT before proceeding. NOTE: On Cherokee, engine diagnostic connector is located at left side of engine compartment, near engine controller.
Page 546
Fig. 91: Test 7A - Code 705, Flow Chart (1 of 2)
Page 548
Fig. 94: Test 7A - Code 705, Flow Chart (2 of 2)
Page 549
Fig. 95: Test 7A - Code 705, Schematic Fig. 96: Test 7A - Location of Throttle Position Sensor (TPS)
Page 550
Fig. 97: Test 7A - Code 705, View of TPS Connector Fig. 98: Test 7A - Location of Engine Control Connector (Cherokee)
Page 551
Fig. 99: Test 7A - View of Engine Control Connector (Cavity 22) TEST 8A - CODE 706 - BRAKE SWITCH CIRCUIT NOTE: Perform TEST 1A - VERIFICATION OF THE COMPLAINT before proceeding.
Page 553
Fig. 101: Test 8A - Code 706, Schematic (Cherokee) Fig. 102: Test 8A - TCU 32-Way Connector (Cavity 10, Cherokee) Fig. 103: Test 8A - Location of Brake Switch Connector...
Page 554
Fig. 104: Test 8A - Code 706, Flow Chart Fig. 105: Test 8A - Code 706, Schematic (Cherokee)
Page 555
Fig. 106: Test 8A - View of Engine Controller Connector (Cavity 29) Fig. 107: Test 8A - TCU 32-Way Connector (Cavity 10, Cherokee) Fig. 108: Test 8A - Location of Brake Switch Connector...
Page 556
Fig. 109: Test 8A - View of Brake Switch Connector (Cavity 3) Fig. 110: Test 8A - View of Brake Switch Connector (Cavity 6) TEST 8B - CODE 706 - BRAKE SWITCH CIRCUIT NOTE: Perform TEST 8A - CODE 706 - BRAKE SWITCH CIRCUIT before proceeding.
Page 557
Fig. 111: Test 8B - Code 706, Flow Chart Fig. 112: Test 8B - Code 706, Schematic (Cherokee)
Page 558
Fig. 113: Test 7A - Location of Engine Control Connector (Cherokee) Fig. 114: Test 8B - TCU 32-Way Connector (Cavity 10, Cherokee) TEST 9A - WRONG TCU NOTE: Perform TEST 1A - VERIFICATION OF THE COMPLAINT before proceeding. NOTE: The AW-4 is used only on 4.0L. In earlier years, it was...
Page 559
The DRB-II has determined that the wrong Transmission Control Unit (TCU) has been installed in the vehicle. There are two transmission control units available for the Jeep AW4 transmission. One is for the 4-cylinder 2.5L engine and the other is for the 6- cylinder 4.0L engine.
Page 560
Fig. 117: Test 10A - Location of Transmission Connectors Fig. 118: Test 10A - View of 7-Way Connector (Cherokee) NOTE: See Fig. 115 for wiring diagram.
Installation 1) Install brake switch in retainer. Reconnect brake switch electrical connector. 2) To check brake switch adjustment, slightly depress brake pedal and note operation of brake switch plunger. Brake switch plunger should fully extend when brake pedal free play is taken up and brake application begins.
Page 567
Removal & Installation 1) Disconnect electrical connector at speed sensor located on adapter housing or extension housing. Remove bolt and speed sensor. Remove "O" ring from speed sensor. 2) To install, reverse removal procedure using NEW "O" ring. Tighten bolt to specification. See TORQUE SPECIFICATIONS at end of article.
Page 568
TPS cannot be rotated, reinstall TPS with end of throttle shaft on other side of TPS socket tangs. Fig. 128: Installing Throttle Position Sensor (TPS) Courtesy of Chrysler Corp. TRANSMISSION CONTROL MODULE (TCM) Removal & Installation (Cherokee) Ensure ignition is off. Disconnect electrical connector from TCM, located behind right side of instrument panel.
Removal 1) Raise and support vehicle. Remove drain plug and drain transmission fluid. Remove bolts and oil pan. Remove bolts, oil screen and gasket. 2) Disconnect electrical connectors from valve body solenoid. Mark electrical connector location for reassembly reference if more than one valve body solenoid is being removed.
TRANSFER CASE - NP/NV 242 1993 Jeep Cherokee 1987-96 TRANSFER CASES Jeep - New Venture 242 Cherokee, Comanche, Wagoneer, Grand Wagoneer IDENTIFICATION Transfer case can be identified by an I.D. tag, located on rear case. I.D. tag provides model number, serial number and low range ratio.
Page 571
Removal & Installation 1) Mark front propeller shaft and flange for alignment purposes. Remove front propeller shaft. Remove flange. Discard washer and nut. Using a screwdriver, carefully remove oil seal. Ensure seal contact surface is clean. 2) Apply ATF to seal lip and yoke seal surface. Install oil seal and flange with new washer and nut.
Page 572
intermediate clutch shaft snap ring from mainshaft. 5) Remove clutch shaft thrust ring. Remove intermediate clutch shaft. Remove differential retaining snap ring. Remove differential assembly. Remove differential needle bearings and thrust washers from mainshaft. Remove low range fork and hub. 6) Remove shift sector.
Page 573
1) Clean all parts with solvent. Dry with compressed air. Replace all oil seals, "O" rings and snap rings. Check all parts for wear or damage. Replace all worn or damaged parts. Apply Dexron II to all parts before installing. 2) Inspect low range annulus gear inside front case.
Page 574
"O" ring in oil pump. Install oil pick-up tube and screen. Ensure screen is properly positioned. See Fig. 2. 12) Install magnet in front case. Apply 1/8" bead of silicone sealant to front case mating surface. Assemble case halves together. Tighten to specification.
Page 576
TRANSFER CASE - OVERHAUL (207/231) 1993 Jeep Cherokee 1983-96 TRANSFER CASES Chrysler Corp., GM Corp., Jeep - New Process 207 & 231 Dodge; B1500 & Dakota GMC/Chevrolet; "T" Series (Blazer & Jimmy) Jeep; Cherokee, Comanche, Grand Cherokee, Wagoneer, Wrangler IDENTIFICATION Transfer case can be identified by an I.D.
Page 577
transfer case. Apply 15 in. Hg vacuum to "L". See Fig. 1. Vacuum should be present at "M". Connect a vacuum gauge to "N". Shift to 4WD position. Apply vacuum to "L". Vacuum should be present at "N". If switch fails any test, replace switch. Fig.
Page 578
Will Not Shift Or Difficult To Shift Into Gear Vehicle speed too high; slow vehicle to 2-3 MPH to shift. Vehicle operated too long on dry paved surface; stop vehicle and place in Reverse or Neutral to relieve driveline torque. Ensure transfer case external linkage is not binding.
Installation 1) Clean all old gasket material from transmission and transfer case mating surfaces. Position NEW gasket on transfer case with orientation tab at upper left bolt hole. 2) Install transfer case, aligning splines of input shaft with transmission. Slide transfer case forward until seated against transmission.
Page 580
Fig. 2: Exploded View Of Transfer Case (Model 207) Courtesy of Chrysler Corp.
Fig. 3: Exploded View Of Transfer Case (Model 231) Courtesy of Chrysler Corp. CLEANING & INSPECTION Clean all parts with solvent. Dry with compressed air. Replace all oil seals, "O" rings and snap rings. Check all parts for wear or damage. Replace all worn or damaged parts. If low range annulus gear inside front case is damaged or worn, front case and gear must be replaced as an assembly.
Page 582
Install output shaft front bearing with NEW snap ring. Install output shaft oil seal in front case. Install snap ring on NEW input gear bearing. See Fig. 2 or 3. 2) Press input gear bearing so snap ring is seated against case.
Page 583
Fig. 4: Installing Drive Sprocket Bearings Courtesy of Chrysler Corp. Fig. 5: Identifying Oil Pump Screen Position Courtesy of Chrysler Corp.
Page 586
TRANSMISSION REMOVAL & INSTALLATION - A/T 1993 Jeep Cherokee 1993 TRANSMISSION SERVICING Chrysler Corp. Transmission Removal & Installation Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler MANUAL TRANSMISSION NOTE: For manual transmission replacement procedures, see appropriate article in CLUTCHES. AUTOMATIC TRANSMISSION REMOVAL &...
Page 587
pipes from exhaust manifolds, if necessary. Drain transfer case lubricant. Disconnect speedometer cable from transmission. 3) Disconnect all shift and throttle linkages and wiring from transmission and transfer case. Mark converter drive plate and converter for reassembly. Remove torque converter-to-drive plate bolts.
Page 590
Fig. 1: Adjusting Kickdown (Front) Band Courtesy of Chrysler Corp. LOW-REVERSE (REAR) BAND (TYPICAL) 32RH 1) Raise and support vehicle. Drain transmission fluid and remove oil pan. Locate low-reverse band adjusting screw on rear servo lever. See Fig. 2. Loosen adjusting screw lock nut. Back off lock nut 5-6 turns.
Fig. 2: Adjusting Low-Reverse (Rear) Band (Typical) Courtesy of Chrysler Corp. THROTTLE CABLE With ignition off, fully retract cable plunger. Press cable button down and push cable plunger inward. Rotate throttle lever to wide open throttle position. Cable will ratchet to correct position. Release throttle lever.
column, ensure linkage lash is eliminated by pulling down on shift rod and pushing up on outer bellcrank when tightening jam nuts. 3) Check steering column lock for ease of operation. Ensure engine starts in Neutral or Park only. If starter engages in any drive gear, or does not work in Neutral or Park, check for proper shift linkage adjustment or faulty neutral safety switch.
Page 593
4) To install, disconnect shift linkage from transmission shift lever. Rotate shift lever all the way rearward and then forward 2 detent positions. This is the Neutral position. Install switch assembly. 5) Install adjusting bolt finger tight only. Install lock washer and retaining nut.
Page 594
allow starter operation in Park or Neutral only. 2) To test switch, remove wire harness and test for continuity between center pin of switch and transmission case. Continuity should only exist when transmission is in Park or Neutral. 3) Shift transmission into Reverse. Check for continuity between 2 outer switch terminals.
Page 598
TRANSMISSION REMOVAL & INSTALLATION - A/T 1993 Jeep Cherokee 1993 TRANSMISSION SERVICING Chrysler Corp. Transmission Removal & Installation Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler MANUAL TRANSMISSION NOTE: For manual transmission replacement procedures, see appropriate article in CLUTCHES. AUTOMATIC TRANSMISSION REMOVAL &...
Page 599
pipes from exhaust manifolds, if necessary. Drain transfer case lubricant. Disconnect speedometer cable from transmission. 3) Disconnect all shift and throttle linkages and wiring from transmission and transfer case. Mark converter drive plate and converter for reassembly. Remove torque converter-to-drive plate bolts.
Page 602
Fig. 1: Adjusting Kickdown (Front) Band Courtesy of Chrysler Corp. LOW-REVERSE (REAR) BAND (TYPICAL) 32RH 1) Raise and support vehicle. Drain transmission fluid and remove oil pan. Locate low-reverse band adjusting screw on rear servo lever. See Fig. 2. Loosen adjusting screw lock nut. Back off lock nut 5-6 turns.
Page 603
Fig. 2: Adjusting Low-Reverse (Rear) Band (Typical) Courtesy of Chrysler Corp. THROTTLE CABLE With ignition off, fully retract cable plunger. Press cable button down and push cable plunger inward. Rotate throttle lever to wide open throttle position. Cable will ratchet to correct position. Release throttle lever.
Page 604
column, ensure linkage lash is eliminated by pulling down on shift rod and pushing up on outer bellcrank when tightening jam nuts. 3) Check steering column lock for ease of operation. Ensure engine starts in Neutral or Park only. If starter engages in any drive gear, or does not work in Neutral or Park, check for proper shift linkage adjustment or faulty neutral safety switch.
Page 605
4) To install, disconnect shift linkage from transmission shift lever. Rotate shift lever all the way rearward and then forward 2 detent positions. This is the Neutral position. Install switch assembly. 5) Install adjusting bolt finger tight only. Install lock washer and retaining nut.
Page 606
allow starter operation in Park or Neutral only. 2) To test switch, remove wire harness and test for continuity between center pin of switch and transmission case. Continuity should only exist when transmission is in Park or Neutral. 3) Shift transmission into Reverse. Check for continuity between 2 outer switch terminals.
2.5L 4-CYL - VIN [P] 1993 Jeep Cherokee 1993 CHRYSLER CORP. ENGINES 2.5L 4-Cylinder Jeep: Cherokee, Wrangler ENGINE IDENTIFICATION NOTE: For engine repair procedures not covered in this article, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article in the GENERAL INFORMATION section.
FUEL PRESSURE RELEASE CAUTION: Fuel system is under constant pressure. This pressure must be released before disconnecting or servicing any fuel supply or return system component. Wear proper eye protection when releasing fuel system pressure. Disconnect negative battery cable. Remove fuel filler cap. Remove cap from pressure test port on fuel rail.
Page 611
release system pressure before removing radiator cap or drain cock. Fill radiator completely and install pressure cap. Fill reserve/overflow tank to FULL mark. Operate engine until it reaches normal operating temperature. Shut off engine and allow it to cool. Recheck coolant level in reserve/overflow tank as necessary. Add coolant ONLY when engine is cold.
exhaust manifold. Remove starter. Remove flywheel housing access cover. Remove engine mount through-bolts. Remove upper bellhousing bolts. Loosen lower bellhousing bolts. 6) Lower vehicle. Attach lifting device to engine. Raise engine from front supports. Place support under bellhousing. Remove remaining bellhousing bolts. Lift engine from engine compartment. Installation (All Models) Remove engine mount cushions from brackets to aid alignment of engine and transmission.
manifold. Finger tighten all bolts. Tighten intake manifold bolts to specification in correct sequence. See Fig. 2. Also see TORQUE SPECIFICATIONS table. To complete installation, reverse removal procedure. Fill and bleed cooling system. EXHAUST MANIFOLD Removal Disconnect negative battery cable. Remove intake manifold. See INTAKE MANIFOLD.
tightened to a lower torque than the others. 3) To complete installation, reverse removal procedure. Install all valve train components into their original locations. Refill cooling system. Remove coolant temperature sensor to bleed air from system while filling. Fig. 3: Cylinder Head Bolt Tightening Sequence Courtesy of Chrysler Corp.
Page 615
sprocket retaining bolt. Remove sprockets and chain as an assembly. Remove front cover oil seal. Fig. 4: Aligning Sprocket Timing Marks Courtesy of Chrysler Corp. Installation 1) Turn tensioner lever down to unlock position. Pull tensioner block toward lever to compress spring. Turn lever up to lock position.
Fig. 5: Locating Chain Tensioner Lock Courtesy of Chrysler Corp. 2) Verify proper installation by rotating crankshaft until timing mark on camshaft is at approximately one o’clock position. Timing sprockets are installed correctly if there are 20 timing chain pins between timing marks on both sprockets. 3) Clean all gasket surfaces.
Installation 1) Lubricate push rod ends with Mopar Engine Oil Supplement (4318002). Install push rods into their original locations. Ensure bottom end of each push rod is centered in valve lifter. 2) Lubricate pivot contact area of each rocker arm with engine oil supplement.
Page 618
heater hoses and lower radiator hose at water pump. Remove water pump retaining bolts. Remove water pump. Installation Install water pump. Tighten bolts to specification. See TORQUE SPECIFICATIONS table. Ensure pump turns freely. Ensure belt is installed correctly to prevent engine overheating because water pump rotates in wrong direction.
(.063 mm), or if diameter exceeds specification by .003" (.08 mm), ream valve guide for oversize valve stem. See CYLINDER HEAD table under ENGINE SPECIFICATIONS. Reface valve seats after reaming valve guides. Valve Seats Reface valve seats to specification. Remove only enough metal to provide smooth finish.
wear exists along length of push rod, inspect cylinder head for obstruction. CYLINDER BLOCK ASSEMBLY Piston & Rod Assembly 1) Note locations of arrow on piston crown and oil squirt hole in connecting rod. Position piston and rod assembly on support. See Fig.
Page 621
Measure piston diameter at right angle to piston pin at center line of pin. Piston clearance is difference between measurements. Pistons up to .004" (.10 mm) undersize may be enlarged by knurling or shot peening. Replace pistons if clearance is greater than .004" (.10 mm) or more.
Page 622
Using Plastigage, check bearing clearance. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS. Bearings are available for standard and undersize applications. 2) If necessary, different size upper and lower bearings may be combined to obtain correct oil clearance. Tighten bolts to specification.
rocker arms receive oil through the push rods and lifters. Crankcase Capacity Crankcase capacity is 4 qts. (3.8L) with oil filter change. Oil Pressure ¢ Normal oil pressure should be 25-35 psi (1.8-2.5 kg/cm ) at ¢ 800 RPM or 37-75 psi (2.6-5.3 kg/cm ) at 1600 RPM.
Page 628
4.0L 6-CYL - VIN [S] 1993 Jeep Cherokee 1993 CHRYSLER CORP. ENGINES 4.0L 6-Cylinder Jeep: Cherokee, Grand Cherokee, Wrangler ENGINE IDENTIFICATION NOTE: For engine repair procedures not covered in this article, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article in the GENERAL INFORMATION section.
Page 629
FUEL PRESSURE RELEASE CAUTION: Fuel system is under constant pressure. This pressure must be released before disconnecting or servicing any fuel supply or return system component. Wear proper eye protection when releasing fuel system pressure. Disconnect negative battery cable. Remove fuel filler cap. Remove cap from pressure test port on fuel rail.
Page 630
release system pressure before removing radiator cap or opening drain cock. Add coolant only when engine is cold. Fill radiator completely and install pressure cap. Fill reserve/overflow tank to FULL mark. Operate engine until it reaches normal operating temperature. Shut off engine and allow it to cool. Recheck coolant level in reserve/overflow tank as necessary.
Page 631
4) Remove check valve from power brake booster (if equipped). Disconnect power steering hoses at steering gear (if equipped). Drain power steering pump reservoir. Cap power steering hoses and fittings. 5) Tag and disconnect any remaining hoses or electrical connectors. Raise and support vehicle. Disconnect exhaust pipe from exhaust manifold.
EXHAUST MANIFOLD Removal & Installation Remove exhaust manifold with intake manifold. See INTAKE MANIFOLD. CYLINDER HEAD Removal 1) Disconnect negative battery cable. Drain cooling system. Remove air cleaner and fuel pipe. Remove molded hoses from cylinder head cover. Remove cylinder head cover. 2) Remove rocker arms, bridges, pivots and push rods.
Page 633
Fig. 3: Cylinder Head Bolt Tightening Sequence Courtesy of Chrysler Corp. FRONT COVER OIL SEAL Removal 1) Disconnect negative battery cable. Remove drive belts, fan shroud, fan and hub assembly. Remove accessory drive pulley. Remove vibration damper retaining bolt and washer. 2) Using Puller (8068), remove vibration damper and key.
Page 634
timing mark on camshaft is at approximately one o’clock position. Timing sprockets are installed correctly if 15 timing chain pins are between timing marks on both sprockets. 3) Install NEW front cover oil seal. Cut oil pan gasket tabs even with face of cylinder block. Remove tabs. Remove gasket from oil pan.
Page 635
2) Place lower half of seal into bearing cap No. 7. Coat both sides of the lower seal end tabs w/Jeep Gasket-in-a-Tube, or equivalent. Do not apply sealant to the lip of the seal. Coat the outer curved surface of the lower seal with soap and the lip of the seal w/engine oil.
Page 636
3) Position the lower seal into the bearing cap recess and seat it firmly. Be sure seal is flush with cylinder block pan rail. Apply Loctite 515, or equivalent on rear bearing cap. The bead should be 0.125" (3 mm) thick. Do not apply Loctite 515, or equivalent to lip of seal.
Page 637
cylinder head if warpage exceeds specification or damage exists. See CYLINDER HEAD table under ENGINE SPECIFICATIONS. Valve Springs Use Valve Spring Tester (C-647 or J-22738-02) to test each valve spring. Measure free length of each valve spring. Replace valve springs that do not meet specifications. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.
Page 638
Rocker Arms Inspect pivot and valve stem contact surfaces of each rocker arm. Replace any rocker arm that is scuffed, pitted, cracked or excessively worn. Push Rods Inspect push rods for excessive wear. If wear is excessive because of lack of oil, replace and inspect corresponding valve lifter for excessive wear.
Page 639
installation requires approximately 2000 lbs. (900 kg) of force. Replace connecting rod if noticeably less force is required, or if rod moves on pin. Fitting Pistons Measure cylinder bore 2 5/16" (59 mm) below top of bore. Measure piston diameter at right angle to piston pin at center line of pin.
Page 640
2) Install upper bearing inserts. Install bearing caps and lower inserts. Tighten bearing caps in 3 stages to specification. Rotate crankshaft to ensure freedom of movement after tightening each cap. See TORQUE SPECIFICATIONS TABLE at the end of this article. See CRANKSHAFT, MAIN &...
1/4" X 20 ........114 (13) 5/16" X 18 ........156 (18) Oil Pump Cover Bolts ......70 (8) Valve Cover Bolts ......... 80 (9) (1) - Information is not available from manufacturer. (2) - All bolts except No. 11. Tighten bolt No. 11 to 100 ft.
compressor drive belt. Disconnect clutch coil lead. With refrigerant lines attached, remove compressor mounting bolts and position compressor for service. 2) Using Clutch Hub Holder (6355), remove crankshaft nut. Using Clutch Hub Puller (6354), remove clutch hub and hub clearance shims.
Page 649
and pulley surface. On Laser and Talon, clearance should be .014-.026" (.36-.66 mm). On all models except Laser and Talon, clearance should be .020-.035" (.51-.89 mm). Adjust shim thickness to obtain correct clearance. Install NEW compressor shaft bolt and tighten it to 13 ft. lbs.
Page 650
Fig. 1: Exploded View Of Compressor (Nippondenso 10PA17, 10PA17A & 10PA20 10-Cylinder) Courtesy of Ford Motor Co. SANDEN SD-709 & SD-709P 7-CYLINDER CLUTCH ASSEMBLY Removal 1) Using Spanner (6462), hold clutch and remove compressor shaft nut. Using Puller (6461), remove clutch plate. Remove key from compressor shaft.
Page 651
(.41-.79 mm). If clearance is not within specification, adjust shim thickness to obtain correct clearance. SHAFT SEAL Removal 1) Discharge A/C system using approved refrigerant recovery/recycling equipment. Remove compressor. Drain oil from compressor, and measure amount drained. Remove clutch assembly. 2) Remove key from shaft.
Page 652
and pulley surface. Proper clearance is .013-.025" (.33-.64 mm). Adjust shim thickness to obtain correct clearance. Tighten compressor shaft nut to 13 ft. lbs. (18 N.m). 5) Once compressor shaft nut is tightened, recheck clearance between clutch plate and pulley surface in 4 places. Readjust clearance if necessary.
Always check the underhood A/C specification label or A/C compressor label before adding refrigerant oil to A/C compressor/system. The following types of R-134a refrigerant oil are currently available. Chrysler/Jeep/Eagle PAG (ND8) Refrigerant Oil (82300102) NOTE: Synthetic/PAG oil absorbs moisture very rapidly, 2.3-5.6 percent by weight as compared to a mineral oil absorption rate of .005 percent by weight.
twisted during installation. To prevent damage to lines and fittings, always use 2 wrenches. PLACING SYSTEM IN OPERATION After component service or replacement has been completed, evacuate system thoroughly with a vacuum pump. Charge system with proper amount of refrigerant. See REFRIGERANT OIL & REFRIGERANT SPECIFICATIONS in this article.
Cherokee The mode control lever (upper lever) operates a vacuum switch on the back of the control panel. The vacuum switch controls vacuum to defroster, floor, panel and fresh/recirculated air vacuum motors, as well as a vacuum-actuated heater control valve (water valve). The heater control valve closes when vacuum is applied to it.
BLOWER MOTOR 1) Using an ohmmeter, check resistance between blower motor housing and chassis ground. Zero ohms should be present. If resistance is zero, go to next step. If resistance is more than zero ohms, repair ground connection. 2) Disconnect blower motor connector. Apply battery voltage to blower motor connector.
MAX or NORM position. Check voltage at Light Green wire terminal of low pressure switch connector. If battery voltage is not present, repair circuit between low pressure switch and control panel. 3) If battery voltage is present, check voltage at Dark Blue/Orange wire terminal of low pressure switch connector.
Page 663
Fig. 1: Locating A/C Sensor (Cherokee) Courtesy of Chrysler Corp. A/C THERMOSTAT Removal (Wrangler) Remove evaporator housing. See EVAPORATOR & EVAPORATOR HOUSING under REMOVAL & INSTALLATION. Remove screws holding top and bottom halves of housing. Separate housing halves. Carefully remove A/C thermostat and capillary tube.
Page 664
Fig. 2: Positioning Capillary Tube In Evaporator (Wrangler) (Cross-Sectional View Shown) Courtesy of Chrysler Corp. COMPRESSOR NOTE: System charge can be retained by isolating compressor from rest of system. This eliminates the need to evacuate and recharge system after installation. To isolate compressor, begin removal procedure at step 1).
Installation 1) To install, reverse removal procedure. If system was fully discharged, evacuate and charge system. If compressor was isolated before removal, air must be purged from compressor after service valve and hose assemblies are reconnected to compressor. 2) To purge air, cap the service gauge ports on both service valves.
Page 666
Removal & Installation (Cherokee) On 2.5L, remove condenser and receiver-drier as an assembly. See CONDENSER under REMOVAL & INSTALLATION. On 4.0L, discharge A/C system using approved refrigerant recovery/recycling equipment. Disconnect low pressure switch connector. Remove receiver-drier. To install, reverse removal procedure. Evacuate and charge system. Removal &...
Removal & Installation (Cherokee) Discharge A/C system using approved refrigerant recovery/recycling equipment. Remove coolant reservoir and bracket. Disconnect refrigerant hoses from expansion valve. Disconnect expansion valve from evaporator tubes. Remove expansion valve. To install, reverse removal procedure. Evacuate and charge system. Removal &...
Page 669
Fig. 4: Manual A/C-Heater System Wiring Diagram (Cherokee)
Page 670
Fig. 5: Manual A/C-Heater System Wiring Diagram (Wrangler)
Page 671
* A/C-HEATER SYSTEM UNIFORM INSPECTION GUIDELINES * 1993 Jeep Cherokee GENERAL INFORMATION A/C-Heater System Motorist Assurance Program Standards For Automotive Repair All Makes and Models INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP) CONTENTS Motorist Assurance Program (MAP) OVERVIEW OVERVIEW OF SERVICE REQUIREMENTS & SUGGESTIONS...
Page 672
HEATER HOSES HIGH PRESSURE RELIEF VALVES (HPRV) IDLERS IN-LINE FILTERS METAL FITTINGS METAL LINES MIX AND AIR CONTROL DOORS (BLEND DOORS) O-RINGS ORIFICE TUBES PILOT-OPERATED ABSOLUTES (POAS) PLENUMS PRESSURE CONTROL VALVES PRESSURE SENSORS PULLEYS RADIATORS RECEIVER-DRIERS REFRIGERANT REFRIGERANT OIL RELAYS SEALS SERVICE PORTS SPRING LOCK COUPLINGS...
Page 673
are continually republished. In addition to these, standards for Drive Train and Transmissions have recently been promulgated. Participating shops utilize these Uniform Inspection & Communication Standards as part of the inspection process and for communicating their findings to their customers. The Motorist Assurance Program continues to work cooperatively and proactively with government agencies and consumer groups toward solutions that both benefit the customer and are...
Page 674
or the vehicle manufacturer’s recommended service interval and must be documented. Some conditions indicate that service or part replacement is required because the part in question is no longer providing the function for which it is intended, does not meet a vehicle manufacturer’s design specification or is missing.
service to the system in question, if the repair creates or continues an unsafe condition. Reasons to Suggest Repair or Replacement 1 - Part is close to the end of its useful life (just above discard specifications, or weak; failure likely to occur soon, etc.) 2 - To address a customer need, convenience, or request (to stiffen ride, enhance performance, eliminate noise,...
Application incorrect, affecting air conditioning system performance ..Require repair or replacement. Attaching hardware broken ....Require repair or replacement of hardware. Attaching hardware missing ......Require replacement of hardware. Attaching hardware not functioning .... Require repair or replacement of hardware.
Terminal loose, not affecting performance Suggest repair or replacement. Wire lead burned ..Require repair or replacement. Wire lead conductors exposed ....Require repair or replacement. Wire lead open ..Require repair or replacement. Wire lead shorted ..Require repair or replacement. (1) - Determine cause and correct prior to repair or replacement of part.
Missing ......Require replacement. Noisy ....Suggest repair or replacement. Out of adjustment ....( 1) Require repair or replacement. Seized ....Require repair or replacement. (1) - Follow OEM recommended adjustment procedures. Require repair or replacement if out of specification. ¡...
Threads damaged ..Require repair or replacement. Threads stripped (threads missing) ......Require replacement. Wire lead conductors exposed ....Require repair or replacement. Wire lead corroded ..Require repair or replacement. Wire lead open ..Require repair or replacement. Wire lead shorted ..
missing ......Require replacement of hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Contaminated, affecting performance ......Require replacement. Dessicant bag deteriorated ....( 1) Require replacement. Further inspection required. Dessicant at the end of its useful life (saturated with moisture) ..
Terminal loose, affecting performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement. Wire lead burned ..Require repair or replacement. Wire lead conductors exposed ....Require repair or replacement. Wire lead open ..Require repair or replacement. Wire lead shorted ..
Connector broken ..Require repair or replacement. Connector (Weatherpack type) leaking ..Require repair or replacement. Connector melted, affecting performance ... ( 1) Require repair or replacement. Connector melted, not affecting performance ... ( 1) Suggest repair or replacement. Connector missing ..
Page 710
specification ..Require repair or replacement. Circuit shorted ..Require repair or replacement. Connector melted, affecting performance ... ( 1) Require repair or replacement. Connector melted, not affecting performance ... ( 1) Suggest repair or replacement. Connector missing ....Require replacement.
Page 711
A/C SYSTEM GENERAL SERVICING 1993 Jeep Cherokee 1993 GENERAL SERVICING General Servicing Procedures Jeep USING R-12 & R-134a REFRIGERANT HANDLING/SAFETY PRECAUTIONS 1) Always work in a well-ventilated, clean area. Refrigerant (R-12 or R-134a) is colorless and invisible as a gas. Refrigerant is heavier than oxygen and will displace oxygen in a confined area.
Page 712
IDENTIFYING R-134a SYSTEMS & COMPONENTS To prevent refrigerant cross-contamination, use following methods to identify R-134a based systems and components. Fittings & "O" Rings All R-134a based A/C systems use 1/2" - 16 ACME threaded fittings (identifiable by square threads) and quick-connect service couplings.
Use only specified oil for the appropriate system and A/C compressor. Always check the underhood A/C specification label or A/C compressor label before adding refrigerant oil to A/C compressor/system. See Fig. 2. The following R-134a refrigerant oils are currently available. Jeep Use PAG (ND8) Refrigerant Oil (Part No. 82300102).
NOTE: Synthetic/PAG oils absorb moisture very rapidly, 2.3-5.6% by weight, as compared to a mineral oil absorption rate of .005% by weight. SERVICE EQUIPMENT NOTE: Ensure "O" rings are designed for use with specified refrigerant. Deterioration of "O" rings and system contamination will result if incorrect "O"...
Page 715
Oil Streaked Sight Glass If oil streaks appear on sight glass, a lack of refrigerant may be indicated, and the system’s compressor oil is circulating through the system. Cloudy Sight Glass A cloudy sight glass indicates desiccant contained in receiver-drier or accumulator has broken down and is being circulated through system.
Page 717
Low-Side Gauge The low-side gauge, which may have a Blue identifying feature, is used to measure low-side (suction) pressure. Low-side gauge is also called a compound gauge because it can measure pressure and vacuum. Pressure scale ranges from 0 to 150 psi; vacuum scale ranges from 0 to 30 in.
Page 718
1) Once manifold gauge set is attached to system and test hoses have been purged (if required), system is ready for testing. Place all test hoses, gauge set and other equipment away from all moving parts of engine. 2) Start engine, and turn A/C controls to maximum cooling position.
Page 719
1) Discharge refrigerant from system. 2) Replace receiver-drier, accumulator or desiccant bag. 3) Evacuate system with vacuum pump. 4) Charge system with R-12. 5) Operate system and check performance. DEFECTIVE THERMOSTATIC SWITCH GAUGE READINGS Low Side Gauge - Normal High Side Gauge - Normal Other Symptoms Compressor - Cycles on and off too fast.
Page 720
Other Symptoms Compressor - Cycles at incorrect temperature or pressure. Evaporator - May freeze and restrict airflow if switch is allowing compressor to remain on too long. Fig. 7: Misadjusted Thermostatic Switch or Defective Clutch Cycling Switch Gauge Indications Courtesy of Ford Motor Co. Correction With Thermostatic Switch NOTE: If no adjusting screw is provided, the switch...
Page 721
Adjust thermostatic switch. Correction With Clutch Cycling Switch NOTE: Switch is non adjustable and is mounted on a Schrader valve fitting. Therefore, no system discharge is required. 1) Stop engine and turn air conditioner off. 2) Detach electrical connector from pressure sensing switch at accumulator.
Page 722
Low Side Gauge - Low High Side Gauge - Low Other Symptoms Discharge Air - Warm. Sight Glass - Clear or Oil Streaks. Compressor - Operation may have stopped if system is equipped with a refrigerant pressure sensing switch. Fig. 9: Very Low R-12 Charge Pressure Gauge Indications Courtesy of Ford Motor Co.
Page 723
Discharge Air - Slightly cool Evaporator Inlet Pipe - Sweating or frost build up Testing 1) If evaporator inlet is cool to touch, proceed as follows: Set air conditioner for maximum cooling, and operate the system. Spray liquid R-12 on head of valve or capillary tube (if equipped).
Page 724
Fig. 10: Expansion or "H" Valve Stuck Closed Courtesy of Ford Motor Co. Correction 1) Evacuate system using vacuum pump. 2) Charge system with R-12. 3) Operate system and check performance. ORIFICE TUBE PLUGGED GAUGE READINGS Low Side Gauge - Low High Side Gauge - Low Other Symptoms Discharge Air - Slightly cool.
Page 725
Testing If evaporator inlet pipe after orifice tube and accumulator surface are warm, orifice tube is plugged. Fig. 11: Orifice Tube Plugged Pressure Gauge Indications Courtesy of Ford Motor Co. Correction 1) Evacuate system using vacuum pump. 2) Replace orifice tube. 3) Charge system with R-12.
Page 726
indicated). This test may not be possible on applications where sensing bulb is not accessible. c. If low side vacuum reading is obtained, warm expansion valve diaphragm chamber with hand, then repeat test. Fig. 12: Expansion or "H" Valve Stuck Open Pressure Gauge Indications Courtesy of Ford Motor Co.
Page 727
Operate system and check performance. COMPRESSOR MALFUNCTION GAUGE READINGS Low Side Gauge - High High Side Gauge - Low Other Symptoms Compressor - Noisy. Fig. 13: Compressor Malfunction Pressure Gauge Indications Courtesy of Ford Motor Co. Correction 1) Isolate compressor (if equipped with stem-type service valves) or discharge entire system.
Page 728
Other Symptoms Discharge Air - Warm. High Side Lines - Very Hot. Sight Glass - Bubbles. Fig. 14: Condenser Malfunction or R-12 Overcharge Pressure Gauge Indications Courtesy of Ford Motor Co. Correction 1) Check electric cooling fan operation. 2) Inspect condenser for clogged air passages, bug screen, or other obstructions preventing airflow through condenser.
Evacuate system using vacuum pump. Charge system with R-12. e. Operate system and check performance. JEEP The orifice tube is located in the liquid refrigerant line near the condenser. Orifice tube cannot be replaced as a separate component. If orifice tube is faulty or if compressor is replaced, liquid line must be replaced.
Page 730
recovery/recycling equipment for recovery and recycling of refrigerant. FLUSHING A/C SYSTEM Information is not available from manufacturer. EVACUATING A/C SYSTEM CHRYSLER CORP. 1) Close both valves on manifold gauge set. Connect manifold gauge set to high-side and low-side service valves. See SERVICE VALVE LOCATIONS under SYSTEM SERVICE VALVES.
Page 734
ALTERNATOR - NIPPONDENSO 1993 Jeep Cherokee 1993 ELECTRICAL Chrysler Corp. Alternators - Nippondenso Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION Charging system consists of a Powertrain Control Module (PCM), alternator, CHECK ENGINE light and battery. Voltage regulation is controlled within the PCM and cannot be serviced.
Page 735
alternator. TESTING (ON-VEHICLE) ALTERNATOR OUTPUT Output Wire Resistance (Voltage Drop) Test 1) Ensure battery is charged. Turn ignition off. Disconnect negative battery cable. Connect a 0-150 DC ammeter and a voltmeter (0- 18 volts) to vehicle’s charging system. See Fig. 1. 2) Connect a carbon pile rheostat between battery terminals.
Page 736
negative battery cable. Connect a 0-150 DC ammeter and a voltmeter (0- 18 volts) to vehicle charging system. See Fig. 3. 2) Connect a carbon pile rheostat between battery terminals. Ensure carbon pile is in OFF position before connecting leads. CAUTION: Alternator has 2 field terminals.
Page 737
Fig. 3: Testing Alternator Current Output (Typical) Courtesy of Chrysler Corp. ENTERING ON-BOARD DIAGNOSTICS CAUTION: Before entering on-board diagnostics, check charging system for other problems. See PRELIMINARY CHECKS under TROUBLE SHOOTING. DO NOT connect DRB-II to vehicle with battery charger connected. Damage to DRB-II may result. Reading Trouble Codes Trouble codes may be read by using the CHECK ENGINE light on instrument panel or using DRB-II.
Page 739
1) To diagnose system with DRB-II, DRB-II must be in CHARGING MENU. At CHARGING MENU, fault codes and DRB-II test functions can be used. 2) To get to CHARGING MENU, turn ignition off. Attach DRB-II to engine diagnostic connector. Connector is located in engine compartment, near PCM.
Page 740
ADJUSTMENTS Mode This function allows user to erase fault codes. Function also allows user to reset Emission Maintenance Reminder (EMR) light and mileage. DRB-II Volt/Ohmmeter Mode To access volt/ohmmeter mode of DRB-II, connect Red volt/ohmmeter test lead to Red port, located on right-top side of DRB- NOTE: Because DRB-II is grounded through engine diagnostic connector, only one volt/ohmmeter test is required when using...
Page 741
3) Ensure battery cables, terminals and posts are clean and tight. Perform a battery load test by applying a 300-amp load for 15 seconds. Wait 15 seconds to allow battery to stabilize. Apply a load equal to 50 percent of battery cold cranking rating for 15 seconds and record minimum voltage reading.
Page 742
ohmmeter, check for resistance in field driver circuit alternator harness terminal and cavity No. 20 on PCM connector. See Fig. 4. If resistance is 5.0 ohms or greater, repair short to ground in field driver circuit (Dark Green wire). If resistance is less than 5.0 ohms, replace PCM.
alternator harness. If resistance is less than 10.0 ohms, repair Dark Green wire for short to ground. If resistance is 10.0 ohms or greater, replace alternator. Perform CHARGING VERIFICATION (CH-VER) test. 4) With ignition on and engine off, read voltage. If less than 13.0 volts, replace PCM.
ANTI-LOCK BRAKE SAFETY PRECAUTIONS 1993 Jeep Cherokee GENERAL INFORMATION Anti-Lock Brake Safety Precautions * PLEASE READ THIS FIRST * This article is intended for general information purposes only. This information may not apply to all makes and models. If vehicle is equipped with Anti-Lock Brake System (ABS), refer to...
ANTI-LOCK BRAKE SYSTEM 1993 Jeep Cherokee 1993 BRAKES Chrysler Corp. Anti-Lock - Teves Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION The Teves Mark IV Anti-Lock Brake System (ABS) consists of acceleration switch, Controller Anti-Lock Brake (CAB), ANTI-LOCK warning light, Hydraulic Control Unit (HCU), main relay, master...
air escapes from brake pipe fitting. Repeat procedure for remaining 3 brakelines. 4) Ensure master cylinder reservoir is full. Raise and support vehicle. Bleed all 4 wheel calipers. Attach a clear hose to right rear caliper bleeder valve and submerge other end of hose in container of brake fluid.
Removal & Installation ABS pump/motor relay is located on right side of engine compartment in Power Distribution Center (PDC). Turn ignition off. Remove cover from PDC. Locate and remove ABS pump/motor relay from PDC. See Fig. 1. To install, reverse removal procedure. CONTROLLER ANTI-LOCK BRAKE (CAB) Removal &...
Page 751
Removal & Installation 1) Turn ignition off. Disconnect negative battery cable. Disconnect pedal travel sensor electrical connector. Remove air cleaner and hoses. On Grand Cherokee and Grand Wagoneer, remove windshield washer reservoir. On all models, position a small drain container under master cylinder reservoir hoses. Disconnect master cylinder reservoir hoses at HCU and drain fluid into container.
Page 752
Fig. 6: Locating Pedal Travel Sensor Courtesy of Chrysler Corp. REAR WHEEL SPEED SENSOR Removal 1) Turn ignition off. Raise and fold rear seat to access rear wheel speed sensor connectors. Disconnect rear wheel speed sensor electrical connector. Push rear wheel speed sensor grommet and wire harness through floorpan on vehicle.
TORQUE SPECIFICATIONS. Spin rear axle by hand until cardboard spacer is peeled from sensor face. Air gap adjustment should be correct. Using a brass feeler gauge, check air gap adjustment. Air gap should be .043" (1.1 mm). If air gap is not correct, adjust as necessary. Go to step 4).
Page 754
Fig. 8: Locating CCD Connector (Grand Cherokee & Grand Wagoneer) Courtesy of Chrysler Corp. INTERMITTENTS Most intermittent problems are caused by faulty electrical connections or wiring; however, a sticking relay or solenoid can cause a failure. When intermittent failure is encountered, check for fault messages stored in CAB.
ERASE FAULTS FAULTS ERASED. Faults are now erased. Ignition Cycle Default If no fault codes occur for 50 driving cycles, any existing fault messages will be cleared from CAB memory. A drive cycle occurs when ignition is turned on and vehicle is driven faster than 10 MPH. CONNECTOR IDENTIFICATION CONNECTOR IDENTIFICATION DIRECTORY TABLE ¡...
Page 756
Fig. 10: Identifying ABS Main System Relay Connector Terminals Courtesy of Chrysler Corp. Fig. 11: Identifying ABS Pump/Motor Relay Connector Terminals Courtesy of Chrysler Corp.
Page 757
Fig. 12: Controller Anti-Lock Brake (CAB) Connector Terminal ID Courtesy of Chrysler Corp. Fig. 13: Identifying "G" Switch Connector Terminals Courtesy of Chrysler Corp.
Page 758
Fig. 14: Hydraulic Control Unit (HCU) Connector Terminal ID Courtesy of Chrysler Corp. Fig. 15: Identifying Pump/Motor Connector Terminals Courtesy of Chrysler Corp. SELF-DIAGNOSTIC TESTS...
NOTE: Connector and terminal identification illustrations in following tests are provided courtesy of Chrysler Corp. NOTE: For connector terminal identification in following tests, see CONNECTOR IDENTIFICATION under DIAGNOSIS & TESTING. For wire color and terminal identification, see WIRING DIAGRAMS. TEST 1A READING FAULT MESSAGES Using DRB-II, read fault messages and perform appropriate test listed in FAULT MESSAGES table.
CONTROLLER FAILURE If DRB-II displays CONTROLLER FAILURE, replace Controller Anti-Lock Brake (CAB). Perform VERIFICATION TEST VER-1A. TEST 3A "G" SWITCH NOT PROCESSABLE 1) Ensure "G" switch sensor assembly is properly installed. If not properly installed, repair as necessary and perform VERIFICATION TEST VER-1A.
pushed out, damaged or improperly wired, replace hydraulic control unit. Perform VERIFICATION TEST VER-1A. TEST 5A LEFT FRONT INLET VALVE 1) Disconnect and inspect hydraulic unit 10-pin connector. Repair connector as necessary. Turn ignition on. With DRB-II in voltmeter mode, probe terminal No. 4 (White/Light Green wire) of hydraulic unit connector.
Page 762
VERIFICATION TEST VER-1A. If sensor is okay, turn ignition off. 2) Disconnect and inspect CAB 55-pin connector. Repair connector as necessary. Turn ignition on. With DRB-II in voltmeter mode, probe terminal No. 48 (Red wire) of CAB connector. If voltage is present, repair short to battery in Red wire.
and inspect CAB 55-pin connector. Repair connector as necessary. With DRB-II in ohmmeter mode, probe terminal No. 4 of hydraulic unit connector. If resistance is less than 5 ohms, repair short to ground in White/Black or White/Red wire. Perform VERIFICATION TEST VER-1A. 3) If resistance is less than 5 ohms, check resistance of between terminal No.
Page 764
4) If resistance is 900-1300 ohms, replace CAB. Perform VERIFICATION TEST VER-1A. If resistance is not 900-1300 ohms, disconnect and inspect left rear wheel speed sensor connector. Using an external ohmmeter, check resistance between left rear wheel speed sensor connector terminals. If resistance is not 900-1300 ohms, replace wheel speed sensor.
Page 765
CAB 55-pin connector. Perform VERIFICATION TEST VER-1A. TEST 11E LEFT REAR SENSOR CIRCUIT FAILURE 1) On Cherokee and Wrangler, repair open in Light Green/Dark Blue wire. Perform VERIFICATION TEST VER-1A. On Grand Cherokee and Grand Wagoneer, disconnect and inspect Black ABS 8-pin disconnect connector.
Page 766
3) Temporarily replace ABS main relay with another 5-terminal relay from PDC. Using DRB-II, erase ABS fault messages. Cycle ignition off and on. Using DRB-II, read ABS fault messages. If MAIN RELAY/POWER CIRCUIT FAILURE message is displayed, go to next step. If fault is not displayed, replace ABS main relay.
Page 767
(blows), replace hydraulic control unit. Perform VERIFICATION TEST VER-1A. Fig. 16: Measuring ABS Pump/Motor Relay Resistance TEST 13C MAIN RELAY/POWER CIRCUIT FAILURE 1) Ensure DRB-II is NOT in TEVES ABS DIAGNOSTIC MODE. Road test vehicle, making several ABS stops. Inspect ABS fuse in PDC. If fuse is okay (does not blow), ABS system is operating properly at this time.
Page 768
PEDAL TRAVEL SENSOR CIRCUIT 1) Inspect pedal travel sensor connector. Sensor is located on right side of brake booster. If connector is disconnected and/or damaged, repair connector as necessary and perform VERIFICATION TEST VER-1A. If connector is properly connected and NOT damaged, go to next step.
Page 769
connector. Repair connector as necessary. With DRB-II in voltmeter mode, probe Red/Dark Green wire (Red/Dark Blue wire on Grand Cherokee and Grand Wagoneer or Red/Brown wire on Wrangler) at ABS pump/motor relay socket terminal "B". If voltage is more than 9 volts, go to next step.
Page 770
Grand Wagoneer or Tan wire on Wrangler) for a short to ground. Perform VERIFICATION TEST VER-1A. If resistance is more than 5 ohms, go to next step. 3) Using an external ohmmeter, check ABS pump/motor relay diode. Attach ohmmeter positive and negative leads as shown. See Fig.
Page 771
Wrangler) at ABS pump/motor 4-pin harness connector. If voltage is more than 9 volts, go to next step. If voltage is less than 9 volts, repair open Tan/Black wire (Brown/White wire on Grand Cherokee and Grand Wagoneer or Tan wire on Wrangler) to 4-pin harness connector. Perform VERIFICATION TEST VER-1A.
Page 772
Fig. 18: Checking ABS Pump/Motor Sensor Resistance TEST 16A RIGHT FRONT INLET VALVE 1) Disconnect and inspect Hydraulic Control Unit (HCU) 10-pin connector. Repair connector as necessary. Turn ignition on. With DRB- II in voltmeter mode, probe White/Tan wire (White/Orange wire on Grand Cherokee and Grand Wagoneer or White/Yellow wire on Wrangler) at HCU 10-pin harness connector.
Page 773
White/Tan wire (White/Orange wire on Grand Cherokee and Grand Wagoneer or White/Yellow wire on Wrangler) between CAB connector terminal No. 38 and HCU 10-pin harness connector. If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open White/Tan wire (White/Orange wire on Grand Cherokee and Grand Wagoneer or White/Yellow wire on Wrangler).
connector. Repair connector as necessary. Turn ignition on. With DRB- II in voltmeter mode, probe Dark Green/White wire at HCU 10-pin harness connector. If no voltage is present, go to next step. If any voltage is present, repair Dark Green/White wire for a short to battery power.
TEST 19A RIGHT FRONT SENSOR 1) Inspect right front wheel speed sensor for damage. If sensor is okay, go to next step. If sensor is damaged, repair or replace as necessary. Perform VERIFICATION TEST VER-1A. 2) Inspect right front wheel speed sensor tone (pulse) ring for damaged teeth or excessive runout.
Page 776
wire (Yellow wire on Wrangler) at CAB connector terminal No. 45. With DRB-II in ohmmeter mode, measure resistance of Yellow wire (Yellow/Dark Blue wire on Wrangler) at right rear wheel speed sensor harness connector. If resistance is less than 5 ohms, perform TEST 20E.
Page 777
TEST 20E RIGHT REAR SENSOR CIRCUIT FAILURE 1) On Wrangler, repair open Yellow/Dark Blue wire to right rear wheel speed sensor. Perform VERIFICATION TEST VER-1A. On all others, disconnect and inspect Black ABS 8-pin disconnect connector. On Cherokee, connector is located on transmission hump near firewall. On Grand Cherokee and Grand Wagoneer, connector is located behind left side kick panel.
main relay removed. 2) Turn ignition off. With DRB-II in ohmmeter mode, probe Black/Tan ground wire (Black ground wire on Grand Cherokee and Grand Wagoneer) at ABS main relay socket. If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open Black/Tan ground wire (Black ground wire on Grand Cherokee and Grand Wagoneer).
Page 779
3) If voltage is less than 9 volts, repair open in Light Green/Yellow wire (Cherokee and Grand Cherokee and Grand Wagoneer) or Yellow/Dark Green wire (Wrangler). Perform VERIFICATION TEST VER-1A. If voltage is more than 9 volts, turn ignition off. With DRB-II in ohmmeter mode, probe terminal No.
VER-1A. If brake pedal "drop" was felt when valve was actuated, road test vehicle for a minimum of 5 minutes and perform several anti-lock braking stops. 7) Using DRB-II, read fault messages. If DRB-II displays any faults, perform TEST 1A. If DRB-II displays no faults, system is operating properly.
ANTI-THEFT SYSTEM 1993 Jeep Cherokee 1993 ACCESSORIES & EQUIPMENT Chrysler Corp. Anti-Theft System Jeep; Cherokee DESCRIPTION & OPERATION The Vehicle Theft Alarm (VTA) Module is a logic controlled device that monitors vehicle doors, hood, liftgate and ignition tampering. Alarm activates by sounding horn, flashing all external lights and preventing vehicle engine from running.
Cycle ignition switch to RUN position. Horn will sound and also take VTA out of self-test mode. Activate remote keyless entry in both lock and unlock directions. 3) Horn not sounding after any of the above operations indicates a switch failure, lack of input signal to VTA module or internal failure of module.
Page 786
Fig. 3: Identifying Mechanical Instrument Cluster Connector Courtesy of Chrysler Corp. Fig. 4: Identifying Powertrain Control Module Connector Courtesy of Chrysler Corp. Fig. 5: Identifying Remote Keyless Entry Module Connector Courtesy of Chrysler Corp. Fig. 6: Identifying Vehicle Fuse Block Courtesy of Chrysler Corp.
Page 787
Fig. 7: Identifying Vehicle Relay Center Courtesy of Chrysler Corp. Fig. 8: Identifying Vehicle Theft Alarm Module Connector Courtesy of Chrysler Corp. TESTING NOTE: In the following tests, illustrations are courtesy of Chrysler Corp. For connector terminal identification, see the CONNECTOR IDENTIFICATION table. For wiring diagrams, the appropriate chassis wiring diagram in WIRING DIAGRAMS article in ENGINE PERFORMANCE section.
Page 788
disconnecting or connecting any module connector. Once connector is disconnected, ignition can be turned on. NOTE: There are no diagnostic or trouble codes for Vehicle Theft Alarm system. Only symptom diagnosis and repair are provided by the manufacturer. USING DRB-II NOTE: Although other scan testers are available, manufacturer recommends using DRB-II (Diagnostic Readout Box II) to...
Page 789
Fig. 10: Identifying Relay Center Location 3) If security light flashes constantly, go to TEST 3A. If security light does not flash, switch VTA status to diagnostic using DRB-II. If DRB-II does not display TURN IGNITION KEY TO ACC. POSITION, go to TEST 4A.
Page 790
TEST 1B - TESTING SYSTEM FUNCTION NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table. For appropriate wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. Ensure ignition is off. Turn left door lock to UNLOCK position and turn ignition on.
Page 791
wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. 1) Remove fuse No. 4 from fuse block and inspect. If fuse is open (NG), check resistance between terminal No. 8 (Dark Blue/ White wire) of VTA module connector using DRB-II. If resistance is less than 5 ohms, repair shorted wire.
Page 792
Fig. 12: Identifying Remote Keyless Entry Module Location 2) Using DRB-II, check voltage at arm sense circuit terminal No. 6 (Pink/Orange wire). If voltage is more than one volt, repair shorted arm sense (Pink/Orange wire). Perform TEST VER-1. If voltage is less than one volt, replace remote keyless entry module.
Page 793
(right side of receptacle) with DRB-II. If voltage is less than 10 volts, repair open circuit between fuse receptacle and terminal No. 8 (Dark Blue/White wire) of VTA module connector. Perform TEST VER-1. If voltage is more than 10 volts, repair open circuit between pin No. 12 (Dark Blue wire) of VTA module connector and terminal No.
Page 794
If resistance is more than 5 ohms, repair open horn control circuit (Black/Red wire). Perform TEST VER-1. 7) If resistance is less than 5 ohms, connect a jumper wire between terminals No. 1 (Pink/Light Green wire) and No. 4 (Dark Green/Red wire) of horn relay receptacle.
Page 795
indicator light illuminates, repair security indicator light control (Black/Orange wire) for short to ground. Perform TEST VER-1. If security indicator light does not illuminate, replace VTA module. Perform TEST VER-1. TEST 8A - REPAIRING PARKING LIGHT CIRCUIT NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table.
Page 796
using DRB-II. 6) If resistance is less than 5 ohms, repair VTA relay control circuit wire for short to vehicle ground. If resistance is more than 5 ohms, check resistance between terminal No. 5 (Tan/Pink wire) of VTA relay control receptacle and terminal No. 18 (Tan/Pink wire) of VTA module connector using external ohmmeter.
Page 797
not display closed (CLSD), go to TEST 9B. If DRB-II displays closed (CLSD) status, disconnect left front door jamb switch. If status screen does not display closed (CLSD), replace door jamb switch. Perform TEST VER-1. 3) If DRB-II displays closed (CLSD) status, disconnect left rear door jamb switch.
Page 798
in the WIRING DIAGRAMS section. 1) Ensure hood is closed and aligned properly. Using DRB-II, read HOOD AJAR status. If DRB-II does not display closed (CLSD) status, go to TEST 10B. If displays closed (CLSD) status, disconnect hood ajar switch. Using DRB-II, check resistance of hood ajar sense circuit at terminal No.
Page 799
NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table. For appropriate wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. 1) Determine that power doors locks are functioning properly. Repair door locks that are not functioning properly. 2) Disconnect VTA module.
Page 800
TEST 15A - REPAIRING RIGHT DOOR KEY CYLINDER CIRCUIT NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table. For appropriate wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. 1) Using DRB-II, read DOOR KEY CYLINDER SWITCH (DR KEY CYL:) status.
Page 801
Green/Orange wire) of VTA module connector. If resistance is less than 5 ohms, repair disarm sense (Dark Green/Orange wire) for short to ground. Perform TEST VER-1. If resistance is more than 5 ohms, replace VTA module. Perform TEST VER-1. TEST 16A - REPAIRING LIFTGATE KEY CYLINDER CIRCUIT NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table.
Page 802
Fig. 14: Identifying Powertrain Control Module Location TEST 18A - REPAIRING ARM SENSE CIRCUIT FROM REMOTE KEYLESS ENTRY MODULE NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table. For appropriate wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. 1) If malfunction is with disarm system, go to TEST 18B.
TEST VER-1 - VERIFICATION TEST 1) Verify system operation. Ensure all doors, hood and liftgate are closed. Open driver’s door. Remove ignition key from vehicle. Lock all doors with power door lock switch. Close driver’s door. If instrument panel theft alarm "SET" light flashed, system is operational and verified.
Page 804
* BRAKE SYSTEM UNIFORM INSPECTION GUIDELINES * 1993 Jeep Cherokee GENERAL INFORMATION Brake Systems - Motorist Assurance Program Standards For Automotive Repair All Makes & Models CONTENTS OVERVIEW OF MOTORIST ASSURANCE PROGRAM OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS ACCELEROMETERS (G SENSOR OR LATERAL)
Page 805
SHOE HARDWARE SHOES SOCKETS SPEED SENSORS (ELECTRONIC WHEEL AND VEHICLE) STEEL BRAKE LINES STOPLIGHT SWITCHES SWITCHES TIRES TOOTHED RINGS (TONE WHEEL) VACUUM BOOSTERS VACUUM HOSES VALVES WHEEL ATTACHING HARDWARE WHEEL BEARINGS, RACES AND SEALS WHEEL CYLINDERS WIRING HARNESSES INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP) OVERVIEW OF MOTORIST ASSURANCE PROGRAM The Motorist Assurance Program is the consumer outreach effort of the Automotive Maintenance and Repair Association, Inc.
Page 806
satisfied with a repair transaction, the Motorist Assurance Program offers mediation and arbitration through MAP/BBB-CARE and other non- profit organizations. MAP conducted pilot programs in twelve states before announcing the program nationally in October, 1998. During the pilots, participating repair shops demonstrated their adherence to the Pledge and Standards and agreed to follow the UICS in communicating the results of their inspection to their customers.
Page 807
Replacement of the rotor is required because it does not meet design specifications. Some conditions indicate that a service or part replacement is suggested because the part is close to the end of its useful life or addresses a customer’s need, convenience or request. If a customer’s vehicle has one of these conditions, the procedure may be only to suggest service.
Page 808
and make an informed decision about how to proceed. BRAKES SERVICE PROCEDURES REQUIRED & SUGGESTED FOR PROPER VEHICLE OPERATION Some states may have specifications that differ from OEM. Check your local/state regulations. Where state or local laws are stricter, they take precedence over these guidelines. ACCELEROMETERS (G SENSOR OR LATERAL) ACCELEROMETER INSPECTION ¡...
Page 815
of caliper. Piston sticking ....Require rebuilding or replacement of caliper. Slide mechanism sticking ....Require repair or replacement of slide mechanism. (1) - Only required if the hydraulic system must be opened. (2) - Seized is defined as a bleeder screw that cannot be removed after a practical attempt at removing.
Wear indicator device (mechanical) contacts rotor ......( 6) Further inspection required. Worn close to minimum specifications ....( 7) Suggest replacement. Worn to, or below minimum specifications ..... Require replacement. (1) - Identify and repair cause of contamination prior to replacing friction material.
Page 824
(1) - This condition may be normal on some vehicles equipped with anti-lock brakes. (2) - Refer to OEM procedures for adjusting low fluid level. Inspect for brake hydraulic system leaks and friction material wear. (3) - This condition may indicate contaminated brake fluid. See BRAKE FLUID.
Terminal burned, not affecting performance Suggest repair or replacement. Terminal corroded, affecting performance Require repair or replacement. Terminal corroded, not affecting performance Suggest repair or replacement. Terminal loose, affecting performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement.
Page 827
reconditioning ....( 3) Require replacement. Surface is rust-pitted ..Require reconditioning or replacement of rotor according to OEM specifications. Surface is scored ..(4) Require reconditioning or replacement of rotor according to OEM specifications. Thickness variation (parallelism) exceeds OEM specifications ..
Page 829
specifications. Wire lead open ..Require repair or replacement. Wire lead shorted ..Require repair or replacement. (1) - If a sensor is not adjustable, further inspection is required to identify and correct cause. (2) - Determine cause and correct prior to repair or replacement of part.
Check valve grommet deteriorated, not affecting performance Suggest replacement of grommet. Check valve inoperative ... ( 2) Require repair or replacement. Check valve leaking ..Require replacement of check valve. Check valve missing ..Require replacement of check valve.
Page 833
hardware. Attaching hardware not functioning ..Require repair or replacement of hardware. Leaking ....Require repair or replacement. Linkage bent (rear load valves) ... Require repair or replacement of linkage. Linkage broken (rear load valves) ... Require repair or replacement of linkage.
to the conditions that follow, you may suggest rebuilding or replacement of the other wheel cylinder (on the same axle) for preventive maintenance, for example, the part is close to the end of its useful life. Determine the need to rebuild or replace based upon the individual wheel cylinder conditions that follow.
BRAKE SYSTEM 1993 Jeep Cherokee 1993 BRAKES Chrysler Corp. - Disc & Drum Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION Floating caliper disc brake assembly uses a single piston caliper which floats on 2 bolts. As brake pedal is depressed, hydraulic pressure passes through a proportioning valve to brake caliper piston.
Page 839
Bench Bleeding 1) Master cylinder must be bled before installation to prevent excessive amounts of air from entering hydraulic system, creating poor brake operation. 2) Place master cylinder in soft-jawed vise. DO NOT tighten vise enough to damage master cylinder. Install bleed tubes in both outlets of master cylinder.
brakelines. Check for leaks. PRESSURE BLEEDING CAUTION: Front brake metering valve is located in front end of combination valve. Valve stem MUST be pressed inward or held outward slightly to bleed front brakes. 1) Clean master cylinder cap and surrounding area. Remove cap.
ADJUSTMENTS BRAKE PEDAL Brake pedal push rod length is preset by manufacturer. No adjustment is possible. PARKING/EMERGENCY BRAKE Cherokee & Wrangler 1) Adjust rear brakes. See REAR BRAKE SHOES under ADJUSTMENTS . Check cable for binding, kinking or fraying. Replace cable as required.
. Check cable for binding, kinking or fraying. Replace cable as required. 2) Fully apply parking brake. Raise and support vehicle. Mark position of adjusting nut on threaded end of cable tensioner. Tighten adjusting nut about 1/2" (13 mm). Replace tensioner if there are not enough threads for proper adjustment.
assembly. 5) Install brake drum and wheels. Lower vehicle. Make final adjustment by driving vehicle and making one forward stop (complete stop), followed by one reverse stop (complete stop). Repeat procedure 8-10 times to operate automatic adjusters and equalize adjustment. Fig.
TESTING POWER BOOSTER Master Cylinder/Power Booster 1) Start engine, and check power booster vacuum hose for leaks. Repair as required. Stop engine, and place gear selector in Neutral. Pump brake pedal until all vacuum reserve is depleted. 2) Press and hold brake pedal under light foot pressure. If pedal does not hold firm and falls away, master cylinder is leaking internally.
Page 845
FRONT BRAKE CALIPER & BRAKE PADS NOTE: Replace brake pads when lining is 1/32" (.8 mm) from rivet heads. Removal 1) Drain about half of brake fluid from master cylinder reservoir. Raise and support vehicle. Remove front wheels. 2) Place "C" clamp on caliper. Solid end of clamp should contact back of caliper.
Page 846
Raise and support vehicle. Remove front wheels. Remove caliper. See, under REMOVAL & INSTALLATION, FRONT BRAKE CALIPER & BRAKE PADS. Suspend caliper from frame or suspension. Remove retainers securing rotor to hub. Remove rotor from hub. To install, reverse removal procedure. See Fig. 6. Fig.
Page 847
Fig. 8: Rear Drum Brake Assembly (Grand Cherokee & Grand Wagoneer) Courtesy of Chrysler Motors. Installation 1) Lubricate backing plate ledges, anchor pin, cable guide, self-adjuster screw assembly, parking brake lever and lever pivot pin with White lithium grease. See Fig. 7 or 8. 2) Connect parking brake lever to secondary brake shoe with washer and "U"...
cable. Using Brake Shoe Adjustment Gauge (J-21177-01), preset brake shoe adjustment. See REAR BRAKE SHOES under ADJUSTMENTS. Install brake drums. Install wheels, and lower vehicle. Check brake fluid. Road test vehicle. OVERHAUL NOTE: For overhaul, refer to appropriate illustration for exploded view of component.
NOTE: On vehicles with Anti-Lock Brake System (ABS), manufacturer does not recommend overhaul of master cylinder. If defective, replace master cylinder and power brake booster as an assembly. Fig. 10: Exp. View Of 2ndary Piston Components (Exc. Vehicles W/ ABS) Courtesy of Chrysler Motors.
COMPUTER RELEARN PROCEDURES 1993 Jeep Cherokee 1991-93 GENERAL INFORMATION Chrysler Motors Computer Relearn Procedures All Domestic Models INTRODUCTION Vehicles equipped with engine or transmission computers may require a relearn procedure after the vehicle battery is disconnected. Many vehicle computers memorize and store vehicle operation patterns for optimum driveability and performance.
Page 852
Ensure the emergency brake has been set and all accessories are turned off. Start engine and bring to normal operating temperature. Allow vehicle to idle in Neutral for one minute. Initial relearn is complete; process will be completed during normal driving. VEHICLES WITH A-604 TRANSAXLE NOTE: If repairs other than battery replacement have been made to...
Page 853
GENERAL COOLING SYSTEM SERVICING 1993 Jeep Cherokee GENERAL INFORMATION General Cooling System Servicing * PLEASE READ THIS FIRST * The following article is for general information only. Information may not apply to all years, makes and models. See specific article in the ENGINE COOLING section.
REFILLING To prevent air from being trapped in engine block, engine should be running when refilling cooling system. After system is full, continue running engine until thermostat is open, then recheck fill level. Do not overfill system. TESTING THERMOSTAT 1) Visually inspect thermostat for corrosion and proper sealing of valve and seat.
Page 855
complete cooling system. Test components as follows, following tool manufacturer’s instructions. Radiator Cap Visually inspect radiator cap, then dip cap into water and connect to tester. Pump tester to bring pressure to upper limit of cap specification. If cap fails to hold pressure, replace cap. Fig.
COOLING SYSTEM SPECIFICATIONS 1993 Jeep Cherokee 1993 ENGINE COOLING Chrysler Corp. Cooling System Specifications Jeep; Cherokee, Grand Cherokee, Wrangler NOTE: Information for Grand Cherokee and Grand Wagoneer with 5.2L V8 engine is not available from manufacturer. SPECIFICATIONS COOLING SYSTEM SPECIFICATIONS COOLING SYSTEM SPECIFICATIONS TABLE ¡...
CRUISE CONTROL SYSTEM 1993 Jeep Cherokee 1993 ACCESSORIES & EQUIPMENT Chrysler Corp. Cruise Control Systems Jeep: Cherokee, Grand Cherokee, Grand Wagoneer DESCRIPTION & OPERATION The cruise control system is electronically controlled and vacuum operated. The electronic control is integrated into the Powertrain Control Module (PCM) located next to the battery.
Page 858
If a problem is sensed with a monitored circuit, a fault code is stored in PCM. Once codes are known, refer to FAULT CODES to determine questionable circuit. Test circuits and repair or replace components as required. If problem is repaired or ceases to exist, PCM cancels that fault code after 50 ignition on/off cycles.
NOTE: If fault code exists that is not related to cruise control system, see appropriate G - TESTS W/CODES - 2.5L & 4.0L article in the ENGINE PERFORMANCE Section. CHECK ENGINE Light Diagnostic Mode 1) With key inserted in ignition switch, cycle ignition switch to ON position 3 times.
Page 860
" ...." ..... Signal Detected During " ...." ....... Road Load Conditions ..SPEED CONTROL SOLENOID CIRCUITS ..An Open Or Shorted " ...." ..Condition Detected In Cruise Control " ...." ... Vacuum Or Vent Solenoid Circuits ¡...
Page 861
Check for: defective servo, faulty electrical circuit or control switch. CRUISE CONTROL ENGAGES WHEN ENGINE IS STARTED Check for: defective servo, faulty electrical circuit. ERRATIC SPEED OR ENGINE SHUTS OFF Check for: poor engine performance (surge), defective vehicle speed sensor, vacuum leak, faulty servo, faulty PCM. CRUISE CONTROL DISENGAGES ON ROUGH ROAD Check for: brakelight switch out of adjustment, faulty electrical circuit.
CRUISE CONTROL CIRCUIT 1) Disconnect Powertrain Control Module (PCM) connector. On XJ models, PCM is located on drivers side fender. On ZJ models, PCM is located on passenger side firewall. Using external voltmeter, connect negative lead to vehicle ground. 2) Turn ignition on. Check voltage at terminal No. 33. Voltage should be zero volts with cruise control switch in OFF position.
Page 864
turning while pushing. Remove horn bushing, receiver and flexplate. Turn ignition switch to LOCK position and remove steering wheel nut with washer. Scribe alignment mark on steering wheel and steering shaft. 2) Remove vibration damper from steering column hub (if equipped).
Page 865
Fig. 2: Identifying Clockspring Connector Terminals Courtesy of Chrysler Corp. Fig. 3: Identifying Cruise Control Servo Connector Terminals Courtesy of Chrysler Corp.
Page 866
Fig. 4: Cruise Control Switch Connector Terminal ID (XJ Model) Courtesy of Chrysler Corp. Fig. 5: Cruise Control Switch Connector Terminal ID (ZJ Model) Courtesy of Chrysler Corp. Fig. 6: Identifying Power Distribution Center (XJ Models) Courtesy of Chrysler Corp.
Fig. 7: Identifying Fuse Block (ZJ Models) Courtesy of Chrysler Corp. Fig. 8: Powertrain Control Module (PCM) Connector Terminal ID Courtesy of Chrysler Corp. Fig. 9: Identifying Vehicle Speed Sensor Connector Terminals Courtesy of Chrysler Corp. SELF-DIAGNOSTICS...
Page 868
* PLEASE READ THIS FIRST * WARNING: If vehicle is equipped with air bag, air bag must be deactivated before servicing cruise control components on or around steering column. CAUTION: Always turn ignition switch to OFF position before disconnecting or connecting any module connector. NOTE: In following self-diagnostic tests, illustrations are courtesy of Chrysler Corp.
Page 869
Perform TEST SC-VER. If voltage is less than 10 volts, repair open cruise control ON/OFF switch sense circuit (Yellow/Red wire) on XJ models. 6) On ZJ models, remove steering column covers to gain access to cruise control switch connector. Using DRB-II in voltmeter mode, backprobe (with connector connected) ON/OFF switch sense circuit at cruise control switch connector terminal No.
Page 870
TEST SC-2C - CRUISE CONTROL VENT SOLENOID CONTROL CIRCUIT NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table. For appropriate wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. 1) Using DRB-II in voltmeter mode, check vent solenoid control circuit voltage at terminal No.
Page 871
in the WIRING DIAGRAMS section. 1) Using DRB-II, read electronic automatic transmission fault codes. If fault code(s) 50-58 is displayed, go to appropriate article in the TRANSMISSION SERVICE section. If fault code(s) 50-58 is not displayed, turn ignition switch to OFF position. 2) Disconnect Transmission Control Module (TCM) connector.
Page 872
resistance at terminal No. 2 (Black/Light Blue wire) of VSS connector. If resistance is more than 5 ohms, repair open in Black/Light Blue wire to harness splice. Perform TEST SC-VER. If resistance is less than 5 ohms, turn ignition switch to OFF position. 6) Disconnect PCM connector.
Page 873
mode, measure VSS signal resistance at terminal No. 47 (White/Orange wire) of PCM connector. If resistance is less than 5 ohms, repair VSS signal circuit for short to ground. Perform TEST SC-VER. 2) If resistance is more than 5 ohms, measure resistance between terminal No.
Page 874
in the WIRING DIAGRAMS section. 1) Using DRB-II in voltmeter mode, check voltage at both sides of cruise control fuse. If voltage input side of fuse (Dark Blue wire) is less than 10 volts, repair open in Dark Blue wire to cruise control fuse.
Page 875
5 ohms, repair cruise control ON/OFF switch sense circuit short to ground. Replace cruise control fuse. Perform TEST SC-VER. 5) If resistance is more than 5 ohms, check cruise control ON/OFF switch sense resistance at terminal No. 1 (Yellow/Red wire) of brake switch connector output.
Page 876
2) If voltage is more than 10 volts, replace cruise control switch. Perform TEST SC-VER. If voltage is less than 10 volts, determine if vehicle is XJ or ZJ model. If vehicle is XJ model, go to step 6). If vehicle is ZJ model, backprobe (with connector connected) resume switch sense circuit voltage at terminal No.
Page 877
voltage measures less than 10 volts, replace the PCM module. Perform TEST SC-VER. 6) Disconnect PCM module. Inspect connector and clean and repair as needed. Turn ignition on. Using DRB-II in voltmeter mode, check cruise control set switch sense circuit voltage at terminal No. 48 (Brown/Red wire) of PCM connector.
Page 878
between cruise control switch connector terminal No. 1 (Yellow/Red wire) and terminal No. 4 (Brown/Red wire). If resistance is 5890-6510 ohms, replace PCM. Perform TEST SC-VER. If resistance is not 5890-6510 ohms, replace cruise control switch. Perform TEST SC-VER. TEST SC-8B - TESTING CLOCKSPRING CIRCUIT FOR SHORTS NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table.
Page 879
4) If resistance is less than 5 ohms, repair ON/OFF switch sense circuit for short to ground between brake switch and servo. Replace cruise control fuse. Perform TEST SC-VER. If resistance is more than 5 ohms, replace brake switch. Replace cruise control fuse. Perform TEST SC-VER.
Page 880
in White/Pink or Brown wire between the brake switch and the PCM. Perform TEST SC-VER. If resistance is more than 5 ohms, replace PCM. Perform TEST SC-VER. 3) Check brake switch adjustment. If brake switch is adjusted correctly, replace brake switch. Perform TEST SC-VER. If brake switch is not adjusted correctly, adjust brake switch.
Page 881
NOTE: For connector terminal identification, refer to the CONNECTOR IDENTIFICATION table. For appropriate wiring diagram, see appropriate chassis wiring diagram in the WIRING DIAGRAMS section. 1) Disconnect Park/Neutral switch connector at transmission. Inspect connector and clean and repair as needed. Using DRB-II, read cruise control inputs monitor.
Page 882
RPM/SPD ..RPM/Vehicle Speed Ratio Is Not Constant SPEED ....Vehicle Speed As Read By Vehicle " ....... Speed Sensor Is Less Than 35 MPH ....... Engine RPM Is Excessively High SOL/FLT ... Fault In Servo Vent Or Vacuum Solenoid "...
DEFOGGER - REAR WINDOW 1993 Jeep Cherokee 1993 ACCESSORIES & EQUIPMENT Chrysler Corp. Rear Window Defoggers Jeep; Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION & OPERATION System consists of 2 vertical bus bars and horizontal rows of heating elements fused to inside of rear glass. On Cherokee, power circuit to grid is protected by fuse No.
Page 884
apply 12 volts to switch terminal No. 1. Using another jumper wire, connect terminal No. 3 of switch to ground. If switch indicator lights, go to next step. If indicator does not light, replace switch. 2) Remove jumper wires. Connect an ohmmeter between switch terminals No.
1) Disconnect defogger relay connector. Turn ignition switch to RUN position. Measure voltage at relay connector terminal No. 4 (Cherokee and Wrangler) or No. 5 (Grand Cherokee and Grand Wagoneer). Battery voltage should be present. If battery voltage is not present, repair open circuit to fuse No.
break. 3) Carefully remove masking tape from grid line. Allow epoxy to cure 24 hours at room temperature or use a heat gun for 15 minutes. Hold gun about 10" from damaged area. Fig. 3: Repairing Defogger Grid Courtesy of Chrysler Motors. REMOVAL &...
Page 888
* DRIVETRAIN SYSTEMS UNIFORM INSPECTION GUIDELINES * 1993 Jeep Cherokee GENERAL INFORMATION Drivetrain/Transmission Motorist Assurance Program Standards For Automotive Repair All Makes and Models INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP) CONTENTS OVERVIEW OF MOTORIST ASSURANCE PROGRAM OVERVIEW OF SERVICE REQUIREMENTS & SUGGESTIONS...
Page 889
FLANGES FLEX PLATES FLUID LEVEL INDICATORS FLUIDS AND LUBRICANTS FLYWHEELS FORCE MOTORS GUIDES HALF SHAFTS HOSES, LINES AND TUBES HOUSINGS (BELL, CASE, TAIL (EXTENSION) AND AUXILIARY) INTERMEDIATE SHAFT SUPPORT BEARINGS KEY INTERLOCK SYSTEMS LIMITED SLIPS LINES LINKAGES (EXTERNAL) LOCKING HUB ASSEMBLIES LOCKING HUB CONTROL KNOBS LUBRICANTS METAL-CLAD SEALS...
Page 890
VEHICLE SPEED SENSORS VENTS VIBRATION DAMPERS WHEEL ATTACHMENT HARDWARE WHEEL SPEED SENSORS WIRING HARNESSES AND CONNECTORS YOKES AND SLIP YOKES INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP) OVERVIEW OF MOTORIST ASSURANCE PROGRAM The Motorist Assurance Program is the consumer outreach effort of the Automotive Maintenance and Repair Association, Inc. (AMRA).
Page 891
has been incorporated which includes the "mystery shopping" of outlets. We welcome you to join us as we continue our outreach... with your support, both the automotive repair industry and your customers will reap the benefits. Please visit MAP at our Internet site www. motorist.org or contact us at: 1444 I Street, NW Suite 700...
Example: An exhaust pipe is rusted, corroded or weak, but no leaks are present. In this case, the exhaust pipe has not failed. However, there is evidence that the pipe may need replacement in the near future. Replacement of the pipe may be suggested for the customer’s convenience in avoiding a future problem.
Page 893
NOTE: Whenever transmission or drivetrain service is performed that affects the suspension alignment, for example, removing the engine cradle, it is required that the alignment be checked and corrected if necessary. AUTOMATIC TRANSMISSION/TRANSAXLE ASSEMBLIES AUTOMATIC TRANSMISSION/TRANSAXLE ASSEMBLY INSPECTION ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ Condition Code Procedure...
refer to the component listing in this document. ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ TRANSFER CASE ASSEMBLIES TRANSFER CASE ASSEMBLY INSPECTION ¡...
Page 895
replacement. Terminal corroded, affecting performance Require repair or replacement. Terminal corroded, not affecting performance Suggest repair or replacement. Terminal loose, affecting performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement. (1) - Determine cause and correct prior to repair or replacement of part.
Page 898
Attaching hardware threads damaged ..Require repair or replacement of part with damaged threads if available; otherwise, replace bushing. Attaching hardware threads stripped (threads missing) ....Require replacement of part with stripped threads if available; otherwise, replace bushing. Binding ....
Page 899
required. Bracket broken, affecting performance ......Require replacement. Bracket broken, not affecting performance ..No service suggested or required. Bracket corroded, affecting performance Require repair or replacement. Bracket corroded, not affecting performance Suggest repair or replacement. Bracket cracked, affecting performance ....
Page 900
Bracket corroded, not affecting performance Suggest repair or replacement. Bracket cracked, affecting performance .... Require repair or replacement. Bracket cracked, not affecting performance Suggest repair or replacement. Bracket loose, affecting performance .... Require repair or replacement. Bracket loose, not affecting performance Suggest repair or replacement.
Page 903
Condition Code Procedure Bent ........ Require replacement. Broken ....Require repair or replacement. Cracked ....Require repair or replacement. Threads damaged ..Require repair or replacement. Threads stripped (threads missing) ......Require replacement. Worn close to the end of its useful life ..
Page 905
Attaching hardware missing ......Require replacement of hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Clamp corroded, not reusable ......Suggest replacement. Connected incorrectly ....Require repair. Corroded, affecting structural integrity .... Require replacement. Corroded, not affecting structural integrity ..
Page 906
not leaking .... Suggest replacement of CV boot. Cage broken ..... Require repair or replacement of CV joint. Housing damaged to the extent that it no longer performs its intended function ......( 1) Require repair or replacement of CV joint. Housing worn to the extent that it no longer performs its intended function...
Page 907
Condition Code Procedure Application incorrect Require repair or replacement. Cracked ....Require repair or replacement. Distorted ....Require repair or replacement. Missing ......Require replacement. Positioned incorrectly Require repair or replacement. Stepped ....Require repair or replacement. Worn to the extent that it no longer performs its intended function ..
Scored ......Require replacement. Spring rate less than specifications ..... Require replacement. Worn, affecting performance ......Require replacement. Worn beyond specifications ..... Require replacement. Worn close to the end of its useful life ....Suggest replacement. ¡...
performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement. Threads damaged ..Require repair or replacement. Threads stripped (threads missing) ......Require replacement. (1) - Determine cause and correct prior to repair or replacement of part.
Page 919
specification ..Require repair or replacement. Sensor housing cracked .... Suggest replacement. Terminal broken ..Require repair or replacement. Terminal burned, affecting performance ....... ( 2) Require repair or replacement. Terminal burned, not affecting performance Suggest repair or replacement. Terminal corroded, affecting performance Require repair or replacement.
Page 920
Threads damaged ..Require repair or replacement. Threads stripped (threads missing) ......Require replacement. Worn close to the end of its useful life ....Suggest replacement. Worn, affecting performance ......Require replacement. (1) - Inoperative includes intermittent operation. ¡...
Page 924
performance .... Require repair or replacement. Fins damaged, not affecting performance ..No service suggested or required. Internal restrictions Require repair or replacement. Leaking ....Require repair or replacement. Threads damaged ..Require repair or replacement. Threads stripped (threads missing) ....
Page 925
Attaching hardware missing ......Require replacement of hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Bearing cap distorted .... Require replacement. Binding ......Require replacement. Cross (trunion) worn, affecting performance .... Require replacement. Double cardon centering ball damaged ...
DRIVE AXLE - FRONT 1993 Jeep Cherokee 1993 Drive Axles - Front Axles Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION Model 30 axle is used on all 4WD applications. Cherokee uses Selec-Trac 4WD system. Wrangler uses Command-Trac 4WD system. Grand Cherokee and Grand Wagoneer use a full-time 4WD system.
Raise axle into position while guiding coil springs into position. Connect upper and lower control arms to axle. To complete installation, reverse removal procedure. Removal (Wrangler) 1) Raise vehicle. Position supports under frame rails at rear of front springs. Remove wheels. Remove brake calipers and hang aside with wire.
models with Command-Trac, ensure shift collar is correctly positioned on intermediate axle shaft. 2) Ensure outer axle shaft is completely engaged with shift collar and joined with intermediate axle shaft. See Fig. 1. Install shift motor. Ensure fork engages with shaft collar. 3) On all models, lubricate hub bore in steering knuckle with wheel bearing grease.
Page 932
Removal Raise and support vehicle. Remove wheel, caliper and rotor. Remove cotter pin, nut retainer, hub nut and washer. Remove hub-to- knuckle bolts. Remove hub from steering knuckle. See Fig. 3. Installation Apply wheel bearing grease to hub bore in steering knuckle and install hub and bearings.
Page 933
and insert balls into hub raceways. Push high side of hub/cage assembly into housing. Ensure assembly rotates freely in housing. Install shaft and circlip. 2) Pack bearing assembly with molybdenum base CV joint grease. Slide boot over CV joint. Install NEW boot clamps. Check shaft and joint for smooth movement.
DRIVE AXLE - SPICER (DANA) TRAC-LOK 1993 Jeep Cherokee 1993 Drive Axles - Differentials - Spicer (Dana) Trac-Lok Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION The Trac-Lok positive traction differential is a 2-pinion, single-case type. Under normal conditions, torque to each rear wheel is divided evenly.
Page 935
OVERHAUL Disassembly 1) Using 2 screwdrivers, remove pinion snap rings. Using a brass drift and a hammer, remove pinion shaft from case. See Fig. 1. Install Step Plate (C-4487-1) in side gear. Grease centering hole of step plate. Position Gear Rotator (C-4487-4) in pinion shaft hole. Coat threads of Forcing Screw (C-4487-2) with oil.
Page 936
assembly in position. Install rotating tool and forcing screw. 4) Tighten forcing screw and compress clutch packs. Install pinions. Rotate side gear with tool pawl until each pinion is aligned with pinion shaft bore. 5) Install pinion thrust washers. Remove tools. Install pinion shaft.
Page 937
DRIVE AXLE - 7.125", 7.56" (7 9/16") & 8.25" 1993 Jeep Cherokee 1993 Drive Axles 7 1/8", 7 9/16" & 8 1/4" Ring Gears Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION Front and rear drive axle assemblies have hypoid type gears with integral carrier housings.
Page 939
specification. Install pinion shaft spring clips (if equipped). Apply RTV to axle housing cover. Tighten cover bolts to specification. See TORQUE SPECIFICATIONS table. Fill with gear oil. NOTE: On vehicles with Trac-Lok (limited slip) differentials, slowly drive vehicle in 10-12 "figure 8" patterns to distribute lubricant to clutch and bearing assembly.
Page 940
Installation Align spring mounting points, and place axle in position. To install, reverse removal procedure. DIFFERENTIAL CARRIER & PINION Removal (Except Cherokee 8 1/4" Ring Gear) 1) Raise and support vehicle. Remove axle housing cover and drain oil. Index mark drive axle and drive shaft yokes for installation.
Page 941
bearing caps. Remove differential carrier. Remove housing spreader. Check the pinion preload and remove the pinion gear assembly. See PINION SEAL & YOKE. Installation (Except Cherokee 8 1/4" Ring Gear) 1) Install pinion gear, pinion bearings and seal (if removed). Adjust pinion preload. See REASSEMBLY under OVERHAUL. Spread housing as during removal.
Page 942
NOTE: Manufacturer does not recommend overhaul of optional Sure-Grip limited slip differential used on Cherokee with 8 1/4" ring gear. It must be replaced as an assembly. DISASSEMBLY NOTE: On models equipped with Trac-Lok, see DIFFERENTIALS - SPICER (DANA) TRAC-LOK article for overhaul of limited slip unit. Following overhaul procedures apply to drive axle gears.
Page 943
thrust washers. Remove side gears and thrust washers. 3) Remove yoke nut, washer and pinion yoke. Keep pinion nut for pinion depth adjustment during reassembly. Remove pinion gear, pinion bearings and preload shims. Discard collapsible spacer. 4) Remove pinion seal and rear pinion bearing race. Remove and retain pinion depth shim located under rear bearing race.
Page 944
ADJUSTMENTS. Pinion Gear 1) Install oil slinger (front axle). Press rear bearing on pinion gear shaft. Place original shim (or see ADJUSTMENTS) in rear bearing bore, and install rear bearing race. NOTE: Install shim so chamfered side is toward bottom of rear bearing bore.
Page 945
Fig. 6: Removing Drive Axle Carrier Bearings Courtesy of Chrysler Corp. 3) Install shims (if equipped), and press carrier bearings onto carrier. Using heat lamp, heat ring gear to 250 ¢ F (121 ¢ Install ring gear on carrier. Install NEW ring gear bolts (LEFT-HAND thread on Cherokee with 8 1/4"...
Page 946
ADJUSTMENTS NOTE: Ring and pinion gears are serviced as matched set only. They are identified by numbers etched on gear and pinion. See Fig. 7. First number (2 or 3 digits) identifies matched set. Second number on pinion gear (preceded by a "+" sign) is pinion depth variance.
Rear Axle Model 35 ......... 2.095 (53.29) 8 1/4" Ring Gear ........¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ ¡ DETERMINING CORRECT PINION STARTING SHIM 1) If original ring and pinion are being installed, use original shim.
Page 948
1) Place bearing race over each carrier bearing. Install carrier assembly (without ring gear) into axle housing. Install a . 142" (3.60 mm) shim on outer side of each carrier bearing race. 2) Install bearing caps. Tighten bolts finger tight. Mount dial indicator to housing.
backlash. See Fig. 10. Fig. 10: Checking Ring Gear Backlash Courtesy of Chrysler Corp. 3) Backlash should be .005-.009" (.13-.23 mm). To increase backlash, install thinner shim on ring gear side of case and a thicker shim on opposite side of case. To decrease backlash, reverse this step.
2) Mount dial indicator on flange. Position indicator stem against drive side of ring gear. Check backlash every 90 degrees to find point of minimum backlash. Mark each position so backlash readings will be taken with same teeth meshed. Rotate ring gear to point of minimum backlash.
Page 951
8 1/4" Ring Gear ........210 (285) Ring Gear Bolts Except 8 1/4" Ring Gear ......45-60 (61-81) 8 1/4" Ring Gear ......... 70 (95) Wheel Lug Nuts ..........75 (102) INCH Lbs. (N.m) Adjuster Lock Screws (Cherokee, 8 1/4" Ring Gear) ..
DRIVE BELT ROUTING 1993 Jeep Cherokee 1993 ENGINE COOLING Chrysler Corp. Drive Belt Routing Jeep; Cherokee, Grand Cherokee, Wrangler NOTE: Information for Grand Cherokee and Grand Wagoneer with 5.2L V8 engine is not available from manufacturer. SPECIFICATIONS BELT ADJUSTMENT Loosen rear mounting bolts of idler pulley or power steering pump (if equipped).
DRIVE SHAFT & UNIVERSAL JOINTS 1993 Jeep Cherokee 1993 Drive Axles - Drive Shafts & Universal Joints Cherokee, Grand Cherokee, Grand Wagoneer, Wrangler DESCRIPTION Drive shafts are balanced, one-piece, tubular steel shafts with universal joints at each end. Single Cardan universal joints contain a spider, 4 bearing caps with needle bearings, seals and clips.
Page 954
VIBRATION Tires & Wheels Check tire inflation and wheel balance. Check for foreign objects in tread, damaged tread, mismatched treads or tire sizes. Check for tires that are out of round. Replace or repair as necessary. Engine & Transmission Mounts Tighten mounting bolts.
SINGLE CARDAN UNIVERSAL JOINT Disassembly Scribe or paint marks on yokes and drive shaft for reassembly reference. Remove bearing cap retainer clips. Using sockets and vise as a press, remove bearing caps retaining spider to drive shaft and yoke. Remove spider. Inspect caps for cracks or defective needle bearings.
Page 957
* ELECTRICAL SYSTEM UNIFORM INSPECTION GUIDELINES * 1993 Jeep Cherokee GENERAL INFORMATION Electrical System Motorist Assurance Program Standards For Automotive Repair All Makes and Models INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP) CONTENTS OVERVIEW OF MOTORIST ASSURANCE PROGRAM OVERVIEW OF SERVICE REQUIREMENTS & SUGGESTIONS...
Page 959
manufacturer-recommended, maintenance. We encourage participating service and repair shops (including franchisees and dealers) to adopt (1) a Pledge of Assurance to their Customers and (2) the Motorist Assurance Program Standards of Service. All participating service providers have agreed to subscribe to this Pledge and to adhere to the promulgated Standards of Service demonstrating to their customers that they are serious about customer satisfaction.
Page 960
Before any service is performed on a vehicle, an inspection of the appropriate system must be performed. The results of this inspection must be explained to the customer and documented on an inspection form. The condition of the vehicle and its components will indicate what services/part replacements may be "Required"...
When presenting suggested repairs to the customer, you must present the facts, allowing the customer to draw their own conclusions and make an informed decision about how to proceed. The following reasons may be used for required and suggested services. These codes are shown in the "Code" column of the MAP Uniform Inspection &...
Page 962
Connector melted ....( 1) Require repair or replacement. Connector missing ....Require replacement. Inoperative ..... ( 2) Require replacement. Linkage bent, affecting performance .... Require repair or replacement of linkage. Linkage bent, not affecting performance Suggest repair or replacement of linkage.
Page 963
hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Connector broken ..Require repair or replacement. Connector (Weatherpack type) leaking ..Require repair or replacement. Connector melted ....( 1) Require repair or replacement. Connector missing ..
Page 964
electrical load ..Suggest upgrade of alternator or removal of excess electrical load. Alternator’s rated output is below OEM specification ...... Require replacement. Attaching hardware broken ....Require repair or replacement of hardware. Attaching hardware missing ......Require replacement of hardware.
minimum specification for vehicle as equipped and test to that specific battery’s CCA. Definition of Terms Battery Performance Testing Testing that determines whether or not a battery meets both vehicle OEM and battery manufacturer’s specifications. Cold Cranking Amp (CCA) Rating The number of amperes a new, fully charged battery at ¢...
Post (top or side) loose ......Require replacement. Post (top or side) melted, affecting performance ... ( 6) Require repair or replacement. Post (top or side) melted, not affecting performance ....... ( 6) Suggest repair or replacement. Specific gravity low ..
Page 968
missing ......Require replacement of hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Connector broken ..Require repair or replacement. Connector melted ....( 1) Require repair or replacement. Connector missing ....Require replacement. Insulation damaged, conductors exposed ..
Page 969
performance ....No service suggested or required. Broken, affecting performance .... Require repair or replacement. Broken, not affecting performance ....No service suggested or required. Corroded, affecting performance .... Require repair or replacement. Corroded, not affecting performance .... Suggest repair or replacement.
Page 970
hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Bulb seized in socket Require repair or replacement. Burned, affecting performance ....... ( 1) Require repair or replacement. Burned, not affecting performance ....... ( 1) Suggest repair or replacement.
Page 971
functioning .... Require repair or replacement of hardware. Base burned, affecting performance ....... ( 2) Require repair or replacement. Base burned, not affecting performance ....... ( 2) Suggest repair or replacement. Base corroded, affecting performance .... Require repair or replacement. Base corroded, not affecting performance Suggest repair or replacement.
Page 972
affecting performance ... ( 2) Suggest repair or replacement. Terminal corroded, affecting performance Require repair or replacement. Terminal corroded, not affecting performance Suggest repair or replacement. Terminal loose, affecting performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement.
Page 974
Wire lead conductors exposed ....Require repair or replacement. Wire lead corroded ..Require repair or replacement. Wire lead open ..Require repair or replacement. Wire lead shorted ..Require repair or replacement. (1) - Refer to manufacturer’s diagnostic trouble code procedure and require repair or replacement of affected component(s).
Page 975
Bracket cracked, affecting performance .... Require repair or replacement. Bracket cracked, not affecting performance Suggest repair or replacement. Bracket loose, affecting performance .... Require repair or replacement. Bracket loose, not affecting performance Suggest repair or replacement. Bracket missing ..... Require replacement.
Page 978
affecting performance Suggest repair or replacement. Terminal loose, affecting performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement. (1) - Determine cause and correct prior to repair or replacement of part. (2) - Inoperative includes intermittent operation or out of OEM specification.
Page 1002
performance .... Require repair or replacement. Terminal loose, not affecting performance Suggest repair or replacement. Wire lead burned ..Require repair or replacement. Wire lead conductors exposed ....Require repair or replacement. Wire lead open ..Require repair or replacement. Wire lead shorted ..
of linkage. Linkage loose, affecting performance .... Require repair or replacement of linkage. Linkage loose, not affecting performance Suggest repair or replacement of linkage. Linkage missing ..... Require replacement. Linkage noisy ... Suggest repair or replacement. Out of adjustment ..
Page 1004
Attaching hardware broken ....Require repair or replacement of hardware. Attaching hardware missing ......Require replacement of hardware. Attaching hardware not functioning .... Require repair or replacement of hardware. Connector broken ..Require repair or replacement. Connector (Weatherpack type) leaking ..
Need help?
Do you have a question about the Cherokee 1993 and is the answer not in the manual?
Questions and answers