NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5]

id0103g8803000

24

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

DESCRIPTION

•  A/C compressor magnetic clutch does not disengage.

POSSIBLE CAUSE

•  PCM, instrument cluster or climate control unit DTC is stored

•  Short to power supply in wiring harness between A/C relay terminal D and magnetic clutch terminal A

•  Magnetic clutch engagement is stuck

•  Climate control unit malfunction (Climate control unit always transmits A/C request signal)

•  A/C relay is stuck closed

•  Short to ground in wiring harness between A/C relay terminal E and PCM terminal 2AF

24	A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY
DESCRIPTION	• A/C compressor magnetic clutch does not disengage.
POSSIBLE CAUSE	• PCM, instrument cluster or climate control unit DTC is stored • Short to power supply in wiring harness between A/C relay terminal D and magnetic clutch terminal A • Magnetic clutch engagement is stuck • Climate control unit malfunction (Climate control unit always transmits A/C request signal) • A/C relay is stuck closed • Short to ground in wiring harness between A/C relay terminal E and PCM terminal 2AF

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 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See DTC INSPECTION [INSTRUMENT CLUSTER].) (See DTC DISPLAY [FULL-AUTO AIR CONDITIONER].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See DTC TABLE [INSTRUMENT CLUSTER].) (See DTC TABLE [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. • 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 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) • Is the magnetic clutch clearance normal?	Yes	Inspect the magnetic clutch to see if it is stuck. (See MAGNETIC CLUTCH INSPECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) Replace the magnetic clutch if necessary. (See MAGNETIC CLUTCH DISASSEMBLY/ASSEMBLY [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
4		No	Adjust the magnetic clutch clearance. (See MAGNETIC CLUTCH ADJUSTMENT [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
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 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) • 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.
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 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) • If a malfunction remains, inspect the related Service 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, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)