NO.19 A/C ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [WL-3]

id0103b5913900

19

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

DESCRIPTION

•  The A/C compressor magnetic clutch does not disengage.

POSSIBLE CAUSE

•  Improper magnetic clutch clearance

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

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

•  Short to power line between A/C relay and pressure switch

•  A/C low/high pressure switch is stuck closed.

•  A/C relay is stuck closed.

Diagnostic procedure

STEP	INSPECTION		ACTION
1	• Connect the M-MDS to the DLC. • Turn the engine switch to the ON position (Engine off). • Retrieve any DTCs. • Is a DTC displayed?	Yes	DTC is displayed: • Go to appropriate DTC test.
1		No	No DTC is displayed: • Go to the next step.
2	• Connect the M-MDS to the DLC. • Access the ACSW PID. • Turn the engine switch to the ON position (Engine off). • Turn the blower switch off. • Does the ACSW PID read ON?	Yes	Go to the next step.
2		No	Inspect for the following: • Short to ground circuit between PCM connector terminal 3C and fan switch • Short to ground circuit between fan switch and blower switch connector terminal Repair or replace if necessary.
3	• Start the engine and run it at idle speed. • Turn the blower switch off. • Measure the voltage at the terminal for the A/C relay connector terminal E. Specification 0 V • Is the voltage correct?	Yes	Inspect for magnetic clutch clearance. Adjust it if necessary.
3		No	Inspect for the following: • Short to ground circuit between PCM connector terminal 4L and A/C relay terminal E • A/C relay is stuck to closed. • Short to power line between A/C relay connector terminal E and A/C pressure switch • Short to power line between pressure switch and A/C compressor magnetic clutch connector Repair or replace if necessary.
4	• Verify the test results. If normal, return to the diagnostic index to service any additional symptoms.

19	A/C always ON or A/C compressor runs continuously
DESCRIPTION	• The A/C compressor magnetic clutch does not disengage.
POSSIBLE CAUSE	• Improper magnetic clutch clearance • Short to ground circuit between PCM and A/C relay • Short to ground circuit between PCM and A/C switch • Short to power line between A/C relay and pressure switch • A/C low/high pressure switch is stuck closed. • A/C relay is stuck closed.