NO.24 A/C ALWAYS ON/A/C COMPRESSOR RUNS CONTINUOUSLY [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513)


BME010300103229

24

A/C always ON or A/C compressor runs continuously

DESCRIPTION

• A/C compressor magnetic clutch does not disengage.

POSSIBLE CAUSE

• Stuck engagement
• A/C relay is stuck closed.
• Short to GND between A/C switch and PCM
• Short to GND circuit between A/C relay and PCM
• A/C relay to magnetic clutch circuit shorts to battery power.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
• Connect the WDS or equivalent to the DLC-2.
• Turn the ignition switch to the ON position (Engine off).
• Retrieve any DTC.
• Is "PASSED" displayed?
Yes
No DTC is displayed:
• Go to the next step.
No
DTC is displayed:
• Go to the applicable DTC inspection.
2
• Start the engine and run it at idle.
• Turn the A/C switch on.
• Remove the A/C relay.
• Does the A/C magnetic clutch disengage?
Yes
Inspect for the following:
• A/C relay is stuck closed.
• Short to GND circuit between A/C relay and PCM terminal 69
- If both items are normal, go to the next step.
No
Inspect if circuit between the A/C relay and the magnetic clutch shorts to battery power circuit.
• If circuit is normal, inspect the magnetic clutch stuck engagement or clearance.
3
• Disconnect the refrigerant pressure switch connector.
• Start the engine and turn the A/C switch on.
Note
• The A/C should not work when the connector disconnected. If the A/C remains working, short to GND circuit may be present.
• Does the A/C remain working?
Yes
Inspect for short to GND circuit between the refrigerant pressure switch and PCM terminal 41.
No
Go to the next step.
4
• Reconnect the refrigerant pressure switch connector.
• Turn off the A/C switch.
Note
• The A/C should not work when the A/C switch is turned off. If the A/C remains working, short to GND circuit may be present.
• Does the A/C remain working?
Yes
Inspect for the following:
• Short to GND circuit between A/C switch and A/C amplifier
• Short to GND circuit between A/C amplifier and refrigerant pressure switch
No
Inspect for stuck closed A/C switch.
5
• Verify test results.
- If normal, return to diagnostic index to service any additional symptoms.
- If malfunction remains, inspect related Service Information and perform repair or diagnosis.
• If vehicle is repaired, troubleshooting completed.
• If vehicle is not repaired or additional diagnostic information is not available, replace or reprogram the PCM.