NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY[L3 Turbo]

id0103b4803000

24

A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY.

DESCRIPTION

A/C compressor magnetic clutch does not disengage.

POSSIBLE CAUSE

•  A/C compressor magnetic clutch engagement is stuck.

•  A/C relay is stuck closed.

•  Short to ground between A/C switch and PCM

•  Short to ground circuit between A/C relay and PCM

•  A/C relay to magnetic clutch circuit shorted to battery power

24	A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY.
DESCRIPTION	A/C compressor magnetic clutch does not disengage.
POSSIBLE CAUSE	• A/C compressor magnetic clutch engagement is stuck. • A/C relay is stuck closed. • Short to ground between A/C switch and PCM • Short to ground circuit between A/C relay and PCM • A/C relay to magnetic clutch circuit shorted to battery power

Diagnostic procedure

STEP	INSPECTION	RESULTS	ACTION
1	Connect the M-MDS to the DLC-2. Turn the ignition switch to the ON position (Engine off). Retrieve any DTCs. Are there any DTCs displayed?	Yes	DTC is displayed: Go to the appropriate DTC test.
1		No	No DTC is displayed: Go to the next step.
2	Start the engine and idle it. 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 ground circuit between A/C relay and PCM terminal 1I. If both items normal, go to the next step.
2		No	Inspect if circuit between A/C relay and magnetic clutch shorts to battery power circuit. If circuit is normal, inspect magnetic clutch for stuck engagement or clearance.
3	Disconnect the refrigerant pressure switch connector. Start the engine and turn the A/C switch on. Note • A/C should not work when disconnecting connector. If A/C remains working, short to ground circuit may be present. Does A/C remain working?	Yes	Inspect for a short to ground circuit between refrigerant pressure switch and PCM terminal 1AU.
3		No	Go to the next step.
4	Reconnect refrigerant pressure switch connector. Turn off A/C switch. Note • A/C should not work when turning A/C switch off. If A/C remains working, short to ground circuit may be present. Does A/C remain working?	Yes	Inspect for the following: • Short to ground circuit between A/C switch and A/C amplifier • Short to ground circuit between A/C amplifier and refrigerant pressure switch
4		No	Inspect the whether A/C switch is stuck closed.
5	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. • If a malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform the repair or diagnosis. ― If the vehicle is repaired, troubleshooting is completed. ― If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.le. Retest.