Download
Share
Print this page
  1. Manuals
  2. Brands
  3. Actron Manuals
  4. Scanner
  5. Code Scanner CP9025
  6. User manual

Actron Code Scanner CP9025 User Manual

Code scanner
Hide thumbs

Advertisement

Quick Links

Download this manual
Congratulations on purchasing your
Actron Code Scanner for accessing
engine trouble codes required for
repairing vehicles equipped with
computers. Your Actron Code Scanner is
made by Actron, the largest and most
trusted name in automotive diagnostic
equipment for the home mechanic. You
can have confidence this product
maintains the highest quality in
manufacturing, and will provide you
years of reliable service.
This instruction manual is divided into
several key sections. You will find
detailed steps on using the Code
Scanner and important information
about trouble code meanings, how a
computer controls engine operation, and
more!
Identifying the problem is the first step in
solving that problem. Your Actron Code
Scanner can help you determine by
accessing the engine computer trouble
codes. Armed with that knowledge, you
can either refer to an appropriate service
manual or discuss your problem with a
knowledgeable service technician. In
either event you can save yourself a lot
of valuable time and money in auto
repair. And feel confident that your
vehicle's problem has been fixed!
TM
1 About Codes ................................... 3
2 When to Read Codes ..................... 5
3 Using Codes ................................... 7
4 Vehicle Preparation ........................ 9
5 Reading Codes ............................. 11
6 Code Meanings ............................ 22
7 Vehicle Preparation ...................... 28
8 Reading Codes ............................. 30
9 Code Meanings ............................ 40
10 Vehicle Preparation ...................... 43
11 Reading Codes ............................. 46
12 Code Meanings ............................ 72
13 Computer Basics .......................... 74
14 Glossary ....................................... 79
1

Advertisement

loading

Related Manuals for Actron Code Scanner CP9025

Summary of Contents for Actron Code Scanner CP9025

  • Page 1: Table Of Contents

    1 About Codes ........3 computers. Your Actron Code Scanner is made by Actron, the largest and most 2 When to Read Codes ..... 5 trusted name in automotive diagnostic 3 Using Codes ........7 equipment for the home mechanic.
  • Page 2 • Always wear approved eye protection. • Always operate the vehicle in a well ventilated area. Do not inhale exhaust gases – they are very poisonous! • Always keep yourself, tools and test equipment away from all moving or hot engine parts. •...
  • Page 3 The computer system in today’s vehicles You obtain trouble codes from the engine does more than control engine operation - it computer memory by using the Actron can help you find problems, too! Special Code Scanner tool. Refer to section 5, 8 testing abilities are permanently pro- or 11 for details.
  • Page 4 The following is a list of publishers who have service manuals for your specific vehicle. Write or call them for availability and prices, specifying the make, style, model year, and VIN (Vehicle Identification Number) of your vehicle. Chilton Book Company Chilton Way Radnor, PA 19089 Toyota Motor Corporation...
  • Page 5 • The “Check Engine” light comes ON “Computerized Engine Controls”, “Electronic Engine Controls”, “Tune-Up Information” or similar. • Vehicle engine is running poorly (for vehicles without a “CHECK ENGINE” LIGHT. • Light ON and stays ON (when the The “CHECK” engine dashboard light engine is RUNNING) tells you when to use the Code Scanner tool.
  • Page 6 • Have the spark plugs, spark plug wires, distributor cap, and rotor (if used) been changed according to the manufacturer’s recommendations? TOYOTA CP9025 • Is the tire pressure correct? Low tire pressure can affect power and gas mileage. Make any necessary repairs before...
  • Page 7 completing repair work. (Refer to “Erasing Trouble Codes after Repair” • “Hard” codes - codes for problems in the “Reading Codes” section for which are present now. your vehicle.) “Hard” problems make the “Check Engine” light come on and stay on. A trouble code is stored in computer memory.
  • Page 8 • Inspect all vacuum hoses for: –Correct routing. Refer HVAC CRUISE to vehicle service CE BOOSTER G GAP BRAKE BOOSTER manual, or Vehicle FUEL PRESS U.S.A. REG. TO TRANS Emission Control MODE Information(VECI) FRONT OF CAR decal located in the engine compartment.
  • Page 9 Important: Complete ALL steps in this section before proceeding to Section 5, “Reading Trouble Codes.” (Exception: Vehicles with Super Monitor Display – Do steps 1 through 6 only.) – Extensive battery use without the 1) Safety First! engine running. Low battery voltage •...
  • Page 10 “SERVICE” connector. There are 2 types... 10) Have a Pencil and • Circular plastic: Paper Ready TOYOTA CP9025 This is usually This is for writing down all bright yellow (or the codes. green), with 2 This completes the vehicle preparation.
  • Page 11 Important: Complete ALL steps in Section 4, “Vehicle Preparation” before reading trouble codes. Toyota uses various computerized engine control systems. • Trouble codes are read by counting flashes on the “CHECK” engine light (or using the Super Monitor Display). • Use the chart below to find the code reading test procedure for your vehicle. * Vehicle must have Super Monitor Display Year Usage...

  • Page 12: Vehicle Preparation

    5) Get Codes from the Flashing 1) Complete ALL steps in Section 4, “CHECK” Engine Light “Vehicle Preparation” • Count flashes to get trouble codes. • Only single digit codes (1 through 8) 2) Access Computer Test Connector are used. Rectangular type: –There is a 1 second pause between •...

  • Page 13: Code Meanings

    • After all trouble codes have been 7) Remove Tool from Connector and written down, finish testing as follows: Replace Connector’s Protective Cover • The engine computer is now back to 6) Turn ignition key OFF normal. TEST RESULTS COMMENTS No indication on You have a problem with the diagnostic circuit “CHECK”...

  • Page 14: Vehicle Preparation

    1) Complete ALL steps in Section 4, Circular test connector: “Vehicle Preparation” • Plug the black jumper wire into both 2) Access Computer Test Connector test connector contacts. (Service manuals refer to these as the “T” and Rectangular type: “E” terminals.) •...

  • Page 15: Code Meanings

    Example of code series 3 and 5: 7) Remove Tool from Connector and Replace Connector’s Protective Cover PAUSE PAUSE • The engine computer is now back to FLASH - FLASH - FLASH normal. (4.5 second pause) Replace cap PAUSE PAUSE PAUSE PAUSE FLASH - FLASH - FLASH - FLASH - FLASH...
  • Page 16 • Remove the indicated fuse for a minimum of 30 seconds. SECONDS – Corolla GT-S (RWD), 1985 Celica, MR2, 1986 MR2 & 1987 Corolla FX-16 (FWD): Remove the “STOP” 15 amp fuse from the fuse block. – 1985 Corolla (RWD) & 1987 MR2: Remove the “AM ”...

  • Page 17: Vehicle Preparation

    Circular test connector: 1) Complete ALL steps in Section 4, “Vehicle Preparation” • Plug the black jumper wire into both test connector contacts. (Service manuals refer to these as the “T” and 2) Access Computer Test Connector “E” terminals.) Rectangular type: •...
  • Page 18 Example of code series 11, 13 and 23: 6) Turn ignition key OFF PAUSE FLASH (pause) FLASH (2.5 second pause, then go to next code) 7) Remove Tool from Connector and Replace PAUSE Connector’s Protective Cover FLASH (pause) FLASH FLASH FLASH •...
  • Page 19 • Remove the indicated fuse for a Look up the code definitions listed in minimum of 30 seconds. “Toyota Code Meanings.” At this point you can either: • Have your vehicle professionally serviced. Trouble codes indicate SECONDS problems found by the computer. •...
  • Page 20 1) Complete Steps 1 Through 5 in • Stored trouble codes are shown on Section 4, “Vehicle Preparation” display as follows... 2) Turn ignition Example of code 32: Display will show Key to ON “E/G 32” or “ENG -32”. Position but •...

  • Page 21: Code Meanings

    TEST RESULTS COMMENTS No indication on Super You have a problem with the Super Monitor Display Monitor Display which needs repair before reading codes. Refer to vehicle service manual. Computer does NOT find a problem. If drive symptom E/G OK or ENG-OK persists, be sure to perform a thorough underhood inspection first.
  • Page 22 • Code meanings can vary with vehicle, model year, engine type and options. • If a code number has more than one definition listed, note that only one definition applies to your vehicle. Consult service manual to get the specific definition for your vehicle. •...
  • Page 23 Starter (STA) signal. Loss of signal from Distributor to System Normal - Oxygen (O ) sensor signal ECU. Faulty Distributor, No malfunction. - Air suction into Exhaust Ignition System components. system. Leak in Air Induction Wiring associated with these system or Air Intake system. parts.
  • Page 24 (EFI) Main relay, or faulty Knock sensor signal - Bad sensor/relay wiring. Knock sensor or faulty System Normal - No sensor wiring. malfunction. Intake Air Temperature sensor signal - Bad Air RPM signal - Bad Cam Airflow meter (AFM) signal Temperature sensor, Air Position sensor, Igniter, - Bad Airflow meter, Main...
  • Page 25 RPM signal - Bad Cam Cold Start Injector. Improper Position sensor, Igniter, Fuel pressure. Faulty Ignition Electronic Control Unit Ignition switch or Integrated system or Distributor. Wiring (ECU) Power supply (B+) - Ignition Assembly (IIA). associated with these parts. Bad Electronic Fuel Injection Faulty Distributor.
  • Page 26 Injector circuit, Ignition Sub Oxygen (O ) sensor system, Air Intake system, signal - Air suction into Airflow meter signal - Bad Exhaust Gas Recirculation Exhaust system, Leak in Air Airflow meter or faulty meter (EGR) system, EGR Vacuum Induction system or in Air wiring.
  • Page 27 Switch Condition - Bad Air Knock sensor Control - Conditioning (A/C) switch, A/ Faulty Knock sensor control C Amplifier, Neutral/Start (ECU) or associated wiring. switch, Throttle Position or , sensor, Accelerator pedal or Knock Control - Faulty Accelerator pedal cable. Knock control (ECU) or Wiring associated with these associated wiring.
  • Page 28 IMPORTANT: Reading trouble codes on 1985 - 1990 (all models) and 1991 Civic, CRX, & Prelude models, requires access to the engine computer. Due to varying mounting locations and methods, some mechanical disassembly may be required! Refer to the Computer Location table in step 3 below. If you are unfamiliar or uncomfortable with the disassembly required, you may want to get help from another person before proceeding.
  • Page 29 4) Access the Computer for Testing • Trouble codes are “read” by noting which LED’s are “ON” (4 LED system) or by observing the flash pattern of a single LED (1 LED system). These LED’s are mounted inside the computer. They can be seen through a “sight window”...
  • Page 30 Important: Complete ALL steps in “Vehicle Preparation” before reading trouble codes. • Honda uses various computerized engine control systems. • Trouble codes are read by: – Observing LED’s (Light Emitting Diodes) built into the engine computer OR ... – Counting flashes on the “CHECK” engine light. •...
  • Page 31 Vehicles With Electronically Controlled Automatic Transaxles • Some vehicles have computer • After engine control system repair, controlled automatic transaxles clear the automatic transaxle (transmissions). computer’s memory by removing the appropriate fuse for 15 seconds. • Typically these transmissions are self- diagnosing, similar to the engine •...
  • Page 32 Each LED has a numeric value. Honda service manuals list several • The left LED has a checks which should be made before value of 8. reading trouble codes. Problems in the areas listed below can cause the • The next LED in line computer to set false or misleading has a value of 4.
  • Page 33 • Trouble codes from zero (no LED’s lit) through 15 (all LED’s lit) are used. • Verify that the • When more than one code is stored: ignition key is in the OFF position. –Each trouble code is presented once. –There is a 2 second pause between •...
  • Page 34 4) Get codes from the flashing LED. • The LED blinks long flashes and short Honda service manuals list several flashes. checks which should be made before reading trouble codes. Problems in the –The duration of the LONG areas listed below can cause the flash is 2 seconds.
  • Page 35 Example: Codes 13 and 21 occur at Multiple Codes... same time. • Depending upon system, trouble (Same failure may have caused both codes are repeated 2 or 3 times in codes.) succession. Sent as... Example: Code 12 PAUSE Sent as... PAUSE PAUSE PAUSE...
  • Page 36 Look up the code definitions listed in • Verify that the Section 9, “Honda Code Meanings.” ignition key is in the OFF position. At this point you can either: • Have your vehicle professionally serviced. Trouble codes indicate problems found by the computer. •...
  • Page 37 Prelude, 1991 (with 2.1L engine) Under the hood, on the left fender, to Honda service manuals list several the rear of the Fuse/Relay Block. This checks which should be made before connector will likely have a protective reading trouble codes. Problems in the cover over the terminals.
  • Page 38 For codes 1 through 10... if the computer sees more than one problem. – Count SHORT flashes to get the code. • Some systems group codes based on Example of code 4: occurrence: Example: Codes 13 and 21 occur at different times.
  • Page 39 7) Write down all displayed Trouble Codes. • Verify that the ignition key is in the OFF position. 8) To view codes a second time, turn the ignition key OFF and then back • Remove the to the ON position. indicated fuse from the fuse block and wait 15 seconds.
  • Page 40 • Code meanings can vary with vehicle, model year, engine type and options. • If a code number has more than one definition listed, note that only one definition applies to your vehicle. Consult service manual to get the specific definition for your vehicle.
  • Page 41 CRK/CYL sensor - Bad CRK/CYL sensor or faulty Throttle Angle (position) Ignition Output Signal - sensor wiring. sensor - Bad Throttle Angle Bad Igniter unit, Ignition coil or , (position) sensor. Faulty or faulty ignition wiring. Automatic Transmission (A/ Crank Angle sensor - Bad NOTE: T) control unit or sensor/ Crank Angle sensor.
  • Page 42 Variable Valve Timing Oxygen (O ) sensor heater Electronic Control (VTEC) - Bad Oxygen sensor or Oil Pressure switch - Bad faulty sensor wiring. VTEC Oil Pressure switch, or , VTEC Spool Valve or faulty Linear Air/Fuel Ratio (LAF) switch/valve wiring. sensor - Bad LAF sensor or faulty sensor wiring.
  • Page 43 2) Test the “CHECK” CHECK Engine Light (Also called IMPORTANT: Reading trouble codes on “CHECK Nissan vehicles requires access to the ENGINE”, or engine computer. Due to varying labeled with a small engine picture.) mounting locations and methods, some mechanical disassembly may NOTE: If vehicle does NOT have a “CHECK”...
  • Page 44 3) Locate the Engine Computer Note: Nissan refers to the engine computer as the ECU (Electronic Control Unit). Axxess 1990 Under Dashboard, behind Center Console Maxima 1985 - 1986 Under Left Side of Dashboard 1987 - 1988 Under Front Passenger Seat 1989 - 1992 Under Dashboard, behind Center Console 1991 - 1992...
  • Page 45 4) Access the Computer for Testing • Trouble codes are “read” by observing the flash patterns of 1 or 2 LED’s (Light Emitting Diodes) mounted inside the computer. These LED’s can be seen through a “sight window” - an opening in the top or side of the computer housing.
  • Page 46 1) Find the number of LED’s used. Nissan uses several engine computer systems and trouble code reading procedures. 2) Read the procedure for counting • Trouble codes are obtained by flashes, page 48. counting LED (Light Emitting Diode) flashes. 3) Follow the test procedure on the •...
  • Page 47 Test Year Usage System LED’s 1984 Stanza EFI ECS 200SX EFI ECS 200SX Turbo, 300ZX, 300ZX Turbo ECCS 1985 Stanza, 200SX EFI ECS 200SX Turbo ECCS Maxima, 300ZX, 300ZX Turbo ECCS 1986 Stanza, 200SX EFI ECS 200SX Turbo ECCS Maxima, 300ZX, 300ZX Turbo ECCS 1986 1/2 Pickup ECCS...
  • Page 48 This system uses a RED and a GREEN This system uses a single RED LED. LED. • The LED blinks long flashes and short flashes. • All Nissan trouble codes are 2 digits –The duration of the LONG flash is .6 long.
  • Page 50 8) When the results from Step 7 are satisfactory, start the engine and observe the RED and GREEN LED’s. • Vehicles with air conditioning: Code 1) Use Selector tool or other means to 44 indicates that the computer turn the Diagnosis Mode Selector system is O.K.
  • Page 51 13)Reconnect the ECU’s harness 10)Turn the connector. ignition switch OFF. 14)Reconnect the negative (-) battery cable. You may have to reset the vehicle clock, radio stations, etc. 11)Disconnect Important: The computer has a the negative “learning” ability to take care of minor (-) battery variations in engine control operation.
  • Page 52 7) Depress and release accelera- tor pedal. 8) Observe the 1) Using the Selector RED and GREEN Tool or other LED’s. means, verify that • Codes 24, and 31 should be the Diagnosis Mode displayed. Selector is in the OFF position. •...
  • Page 53 Look up the code definitions listed in 16)Verify that the Diagnosis Mode Section 12, “Nissan Code Meanings,” Selector is in the OFF position. At this point you can either: • Have your vehicle professionally 17)Remove either serviced. Trouble codes indicate the harness problems found by the computer.
  • Page 54 • Automatic Transmission vehicles: codes 31, and 32 should be displayed. • Note any codes other than 31, and 1) Using the Selector Tool or other means, verify that 7) Depress and the Diagnosis Mode release Selector is in the accelerator OFF position.
  • Page 55 15)When all diagnostic procedures are complete, turn the 16)Verify that the Diagnosis Mode Diagnosis Mode Selector is in the OFF position. Selector to the OFF position, and the ignition switch to the OFF position. 17)Remove either the harness connector from the computer Look up the code definitions listed in (ECU), or the...
  • Page 56 5) Turn the Diagnosis Mode Selector fully CLOCKWISE. 6) Have your pencil and paper ready. 1) Mark the initial setting of the Diagnostic Mode Selector on the computer 7) Observe the RED and GREEN housing. LED’s. IMPORTANT: The • Codes 23, 24, (300ZX Turbo only) Diagnostic Mode and 31 (all vehicles) should be Selector is a potentiom-...
  • Page 57 14)(For 300ZX & 300ZX Turbo only. All others go to Step 16). Drive the Look up the code definitions listed in vehicle at a speed of greater than 6 Section 12, “Nissan Code Meanings,” MPH. Warning: Get the help of At this point you can either: another person for this step! •...
  • Page 58 5) Turn the Diagnosis Mode Selector fully CLOCKWISE. 6) Have your pencil and 1) Mark the initial setting of paper ready. the Diagnostic Mode Selector on the computer housing. 7) Observe the RED and GREEN LED’s. IMPORTANT: The Diagnostic Mode •...
  • Page 59 12)Start the vehicle’s engine. Look up the code definitions listed in Section 12, “Nissan Code Meanings,” 13)Observe the RED and GREEN LED’s. At this point you can either: • On the 300ZX Turbo only, codes 14, • Have your vehicle professionally and 31 should be displayed.
  • Page 60 5) Turn the Diagnosis Mode Selector fully CLOCKWISE. 6) Have your pencil and paper ready. 1) Mark the initial setting of the Diagnostic Mode Selector on the 7) Observe the RED and GREEN computer housing. LED’s. IMPORTANT: The • Codes 23, 31, and 32 should be Diagnostic Mode displayed.
  • Page 61 14) When all diagnostic procedures are Look up the code definitions listed in complete, turn the Section 12, “Nissan Code Meanings,” Diagnosis Mode At this point you can either: Selector fully COUNTERCLOCK- • Have your vehicle professionally WISE, then the ignition switch to serviced.
  • Page 62 5) Turn the Diagnosis Mode Selector fully CLOCKWISE. 6) Have your pencil and paper ready. 1) Mark the initial setting of the Diagnostic Mode Selector on the 7) (For Maxima computer housing. and 300ZX only. If 300ZX Turbo, IMPORTANT: The go to Step 13.) Diagnostic Mode Depress and...
  • Page 63 13) 300ZX Turbo only: Move the gear shift lever from Neutral to all other Look up the code definitions listed in gears and Section 12, “Nissan Code Meanings,” then back to At this point you can either: Neutral. • Have your vehicle professionally serviced.
  • Page 64 10)Observe the RED and GREEN LED’s. • Code 24 should be displayed. • Note any codes other than 24. 1) Start the vehicle’s engine and warm it to normal operating temperature. 11)(For Manual Transmission only. If Automatic Transmission, go to Step 15.) Depress the clutch and move the gear shift lever from Neutral to any other gear and completely...
  • Page 65 17)This completes trouble code retrieval 18)Turn the ignition switch to the ON for automatic position, but do not start the transmission Pickup. engine. Turn the Diagnosis Mode Selector switch OFF, and the ignition 19)Switch the Diagno- switch to the OFF sis Mode Selector position.
  • Page 66 Nissan service manuals list several checks which should be made before 1) Mark the initial setting of reading trouble codes. Problems in the the Diagnostic areas listed below can cause the Mode Selector on computer to set false or misleading the computer codes.
  • Page 67 13)Observe the RED and GREEN 7) Have your pencil and paper ready. LED’s. They will flash sequentially 1 through 5 (1 flash = Mode 1, 2 8) Write down all displayed Trouble flashes = Mode 2, etc.). Codes. 14)When Mode 3 (Trouble 9) This completes Codes) has been trouble code...
  • Page 68 Nissan service manuals list several 1) Turn the ignition checks which should be made before switch ON, but do reading trouble codes. Problems in the not start the areas listed below can cause the engine. computer to set false or misleading codes.
  • Page 69 Look up the code definitions listed in 9) Turn the ignition Section 12, “Nissan Code Meanings,” switch ON, but do not start the At this point you can either: engine. • Have your vehicle professionally serviced. Trouble codes indicate problems found by the computer. 10)Turn the Diagnosis Mode Selector ON.
  • Page 70 Nissan service manuals list several checks which should be made before 1) Mark the initial reading trouble codes. Problems in the setting of the areas listed below can cause the Diagnostic Mode computer to set false or misleading Selector on the codes.
  • Page 71 7) This completes trouble code retrieval on these vehicles. Turn 9) Turn the ignition ignition key OFF. switch ON, but do (The computer will not start the automatically engine. return to normal operation.) 10)Turn the Diagnosis Mode Selector fully 8) IMPORTANT: Turn CLOCKWISE.
  • Page 72 • Code meanings can vary with vehicle, 1) Visual inspections are important! model year, engine type and options. 2) Problems with wiring and connectors • If a code number has more than one are common, especially for intermit- definition listed, note that only one tent faults.
  • Page 73 switch, Electronic Fuel Injection (EFI) relay, Electronic Exhaust Gas Recirculation Fuel Temperature sensor - Concentrated Control System (EGR) sensor - Bad EGR Bad Fuel Temperature sensor (ECCS) relay, Main relay or Control valve, EGR Control or faulty sensor wiring. faulty switch/relay wiring. Solenoid valve, Exhaust Gas or , or ,...
  • Page 74 This section explains the engine computer control system, the types of The main control areas of the computer sensors and how the computer controls are: fuel delivery, idle speed, spark timing • Fuel delivery and emission devices. • Idle speed •...
  • Page 75 example, engine temperature is something the computer needs to know when controlling fuel delivery, spark The computer is permanently pro- timing, idle speed and emission systems. grammed by factory engineers. The The sensor information may be very program is a complex list of instructions important for one engine control function, telling the computer how to control the but only used to “fine tune”...
  • Page 76 fuel is needed for a cold engine.) This information is permanently programmed Not all of the computer outgoing signals into the computer. After the computer go to actuators. Sometimes information knows the engine temperature, it is sent to electronic modules, such as determines the amount of air coming in, ignition or trip computer.
  • Page 77 warm-up, so the computer must operate might stall.) Signals from such systems “open loop” at that time. tell the computer when engine loading is about to occur. Some engines have more than one such throttle air bypass. Later Systems: Throttle position and RPM sensors tell As long as the engine and oxygen the computer when the vehicle is idling.
  • Page 78 mass air flow sensors are used.) Then, Air Injection System the computer adjusts timing according to This system works with the catalytic factory programmed instructions. The convertor. The computer takes outside computer sends a timing signal to an air from an air pump and directs it to the ignition module which eventually creates exhaust manifold as necessary for best the spark.
  • Page 79 See Auxiliary Air Control valve. This sensor measures the amount of air entering the The Air Suction system draws engine and sends a signal to air into the exhaust port to the ECU. Depending upon Air Conditioning. reduce the HC and CO sensor type, the signal may be emissions.
  • Page 80 properly adjust air/fuel mixture atmosphere and causing and ignition timing for varying pollution. During warm engine This switch tells the ECU when engine load and altitude cruise conditions these vapors the clutch is engaged. conditions. are drawn into the engine and burned.
  • Page 81 constantly switching between a small voltage value (close to See Coolant Temperature zero) and a larger value (usually Sensor or Coolant Temperature DIS uses 1 ignition coil per spark 5 volts or greater). Duty cycle is Switch. plug. The coil is mounted directly the percentage of time the to the spark plug (sometimes signal has a large voltage value.
  • Page 82 the amount of air bypassing the throttle plate. Supplies power to the ECCS. Provides vacuum to appropriate Electronic Controlled system or device. Transmission. Used on carbureted vehicles. Operated by the ECU to control the Air/Fuel mixture. See Electronic Control Unit. Senses lift of EGR valve stem (the amount of valve opening).
  • Page 83 See Electronic Spark Advance. This is used on early versions Measures the temperature of of computer controlled engines. fuel in the fuel rail. It is a carburetor which can See Evaporative Emission have its air/fuel delivery system. modified by an electronic signal The return path for current to from the ECU.
  • Page 84 changes with temperature. The hotter the sensor gets, the lower the resistance becomes. The Maintains proper idle speed The LAF sensor is similar to an sensor is located along the path when engine loading changes. Oxygen sensor. of air entering the engine. The ECU uses intake air temperature to provide the proper air/fuel mixture for the desired engine...
  • Page 85 based upon information from various sensors. A type of operating condition, (Pressure - Atmosphere.) See such as “idle mode” or “cruise Atmospheric Pressure Sensor. mode.” See Pressure Regulator Valve. Informs the ECU when the Manual Transmission or Manual gearshift lever is in the Park Transaxle.
  • Page 86 injectors are mounted in the intake manifold. The injectors (Temperature - Air.) See Air See Throttle Position Sensor. are fired individually in the Temperature Sensor. same sequence as the spark plug firing sequence. See Throttle Body Injection. Signals the ECU when the throttle is in the idle position.
  • Page 87 Vehicle Speed Sensor. This sensor, mounted in the transmission, sends a frequency signal to the ECU. The frequency increases as the vehicle moves faster to give the ECU vehicle speed information. See Vehicle Speed Sensor. See Vacuum Switching Valve. See Variable Valve Timing Electronic Control.
  • Page 88 No warranty (expressed or implied) can be made for its accuracy or completeness, nor is any responsibility assumed by Actron or anyone connected with it for loss or damages suffered through reliance on any information contained in this manual or misuse of accompanying product.