Dodge Intrepid Service Manual page 946

LH
A/C COMPRESSOR CLUTCH (Continued)
The compressor clutch engagement is controlled by
several components: the a/c heater control head (ATC
or MTC), the evaporator temperature sensor, the a/c
pressure transducer, the compressor clutch relay, and
the Powertrain Control Module (PCM). The PCM
may delay compressor clutch engagement for up to
thirty seconds. Refer to Electronic Control Modules
for more information on the PCM controls.
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH COIL
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information). The battery must
be fully-charged before performing the following
tests. Refer to Battery for more information.
(1) Connect an ammeter (0 to 10 ampere scale) in
series with the clutch coil terminal. Use a voltmeter
(0 to 20 volt scale) with clip-type leads for measuring
the voltage across the battery and the compressor
clutch coil.
(2) In A/C, mix, defrost and the blower motor
switch in the lowest speed position, start the engine
and run it at normal idle.
(3) The compressor clutch coil voltage should read
within 0.2 volts of the battery voltage. If there is
voltage at the clutch coil, but the reading is not
within 0.2 volts of the battery voltage, test the clutch
coil feed circuit for excessive voltage drop and repair
as required. If there is no voltage reading at the
clutch coil, use a DRBIII
Appropriate Diagnostic Information) for testing of the
compressor clutch circuit. The following components
must be checked and repaired as required before you
can complete testing of the clutch coil:
• Fuses in the junction block and the Power Dis-
tribution Center (PDC)
• A/C heater control head
• Compressor clutch relay
• A/C pressure transducer
• Evaporator temperature sensor
• Powertrain Control Module (PCM).
(4) The compressor clutch coil is acceptable if the
current draw measured at the clutch coil is approxi-
mately 2.2 amperes with the electrical system volt-
age at 11.5 to 12.5 volts. This should only be checked
with the work area temperature at 21° C (70° F). If
system voltage is more than 12.5 volts, add electrical
loads by turning on electrical accessories until the
system voltage drops below 12.5 volts.
(a) If the clutch coil current reading is four
amperes or more, the coil is shorted and should be
replaced.
(b) If the clutch coil current reading is zero, the
coil is open and should be replaced.
scan tool and (Refer to
STANDARD PROCEDURE
INSPECTION
Examine the friction surfaces of the clutch pulley
and the front plate for wear. The pulley and front
plate should be replaced if there is excessive wear or
scoring.
If the friction surfaces are oily, inspect the shaft
and nose area of the compressor for oil. Remove the
felt from the front cover. If the felt is saturated with
oil, the shaft seal is leaking and the compressor must
be replaced.
Check the clutch pulley bearing for roughness or
excessive leakage of grease. Replace the bearing, if
required.
STANDARD PROCEDURE - A/C COMPRESSOR
CLUTCH BREAK-IN
After new clutch installation, cycle the A/C clutch
20 times (5 seconds ON and 5 seconds OFF). During
this procedure, set the system to the A/C mode,
engine rpm at 1500-2000, and high blower speed.
This procedure (burnishing) will seat the opposing
friction surfaces and provide a higher clutch torque
capability.
NOTE: Excessive clutch gap will result in clutch
slippage or non-engagement.
REMOVAL
The refrigerant system can remain fully-charged
during compressor clutch, pulley, or coil replacement.
The compressor clutch can be serviced in the vehicle.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the serpentine drive belt(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL) or (Refer to 7 - COOLING/ACCESSORY
DRIVE/DRIVE BELTS - REMOVAL).
(3) Unplug the compressor clutch coil wire harness
connector.
(4) Remove the bolts that secure the compressor to
the mounting bracket.
(5) Remove the compressor from the mounting
bracket. Support the compressor in the engine com-
partment while servicing the clutch.
(6) Remove the compressor shaft bolt (Fig. 1). A
band type oil filter removal tool can be placed around
the clutch plate to aid in bolt removal.
(7) Tap the clutch plate with a plastic hammer and
remove clutch plate and shim(s) (Fig. 2).
CAUTION: Do not use screwdrivers between the
clutch plate assembly and pulley to remove front
plate as this may damage the front plate assembly.
CONTROLS 24 - 9