Diagnostic Procedure

NO. 24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY DIAGNOSTIC PROCEDURE

STEP	INSPECTION	RESULTS	ACTION
1	VERIFY PCM, INSTRUMENT CLUSTER AND CLIMATE CONTROL UNIT DTC Retrieve the PCM, instrument cluster and climate control unit DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .) (See DTC INSPECTION [INSTRUMENT CLUSTER] .) (See DTC DISPLAY [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE .) (See DTC TABLE [INSTRUMENT CLUSTER] .) (See DTC TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER)] .)
1		No	Go to the next step.
2	DETERMINE IF MALFUNCTION CAUSE IS MAGNETIC CLUTCH OR OTHER Start the engine and idle it. Turn the A/C switch on. Remove the A/C relay. (See RELAY LOCATION .) Does the magnetic clutch disengage?	Yes	Go to Step 5.
2		No	Go to the next step.
3	INSPECT IF MALFUNCTION CAUSE IS MAGNETIC CLUTCH POWER SUPPLY CIRCUIT OR MAGNETIC CLUTCH A/C relay is removed. Switch the ignition off. Disconnect the magnetic clutch connector. Start the engine and idle it. Does the magnetic clutch disengage?	Yes	Inspect for short to power supply circuit between magnetic clutch terminal A and A/C relay terminal D. Refer to the wiring diagram and verify whether or not there is a common connector between magnetic clutch terminal A and A/C relay terminal D. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to power supply.
3		No	Go to the next step.
4	INSPECT MAGNETIC CLUTCH CLEARANCE Verify the magnetic clutch clearance. (See MAGNETIC CLUTCH ADJUSTMENT .) Is the magnetic clutch clearance normal?	Yes	Inspect the magnetic clutch to See if it is stuck. (See MAGNETIC CLUTCH INSPECTION .) Replace the magnetic clutch if necessary. (See MAGNETIC CLUTCH DISASSEMBLY/ASSEMBLY .)
4		No	Adjust the magnetic clutch clearance. (See MAGNETIC CLUTCH ADJUSTMENT .)
5	DETERMINE IF MALFUNCTION CAUSE IS A/C RELAY CONTROL SIGNAL OR A/C REQUEST SIGNAL Access the PCM PID ACCS using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .) Monitor the PID ACCS while turning on and off the air conditioner with switch on the control panel. Is the ACCS PID value always ON?	Yes	Climate control unit always transmits A/C request signal. Replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
5		No	Go to the next step.
6	INSPECT A/C RELAY Inspect the A/C relay. (See RELAY INSPECTION .) Is there any malfunction?	Yes	Replace the A/C relay. (See RELAY LOCATION .)
6		No	Inspect for short to ground circuit between A/C relay terminal E and PCM terminal 2AF. Refer to the wiring diagram and verify whether or not there is a common connector between A/C relay terminal E and PCM terminal 2AF. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to ground.
7	Verify the test results. If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX .) If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform 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.