Passport LX 4WD V6-3165cc 3.2L DOHC MFI (2001)
Compressor Clutch: Testing and Inspection
Compressor Clutch Circuit
A/C Clutch Control Circuit Diagnosis
Circuit Description
When air conditioning and blower fan are selected, and if the system has a sufficient refrigerant charge, a 12-volt signal is supplied to the A/C request
input of the powertrain control module (PCM). The A/C request signal may be temporarily canceled during system operation by the electronic thermostat
in the evaporator case. When the A/C request signal is received by the PCM, the PCM supplies a ground from the compressor clutch relay if the engine
operating conditions are within acceptable ranges. With the A/C compressor relay energized, voltage is supplied to the compressor clutch coil.
The PCM will enable the compressor clutch to engage whenever A/C has been selected with the engine running, unless any of the following conditions
are present:
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The throttle is greater than 90 %.
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The ignition voltage is below 10.5 volts.
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The engine speed is greater than 4500 RPM for 5 seconds or 5400 RPM.
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The engine coolant temperature (ECT) is greater than 125 °C (257 °F).
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The intake air temperature (IAT) is less than 5 °C (41 °F).
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The power steering pressure switch signals a high pressure condition.
Diagnostic Aids
To diagnose an the intermittent fault, check for following conditions:
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Poor connection at the PCM-Inspect connections for backed-out terminals, improper mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
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Damaged harness-Inspect the wiring harness for damage. If the harness appears to OK, observe the A/C clutch while moving connectors and
wiring harnesses related to the A/C. A sudden clutch malfunction will indicate the source of the intermittent fault.
A/C Clutch Diagnosis
