Operation CHARM: Car repair manuals for everyone.

Non-Trouble Code Procedures

A/C Compressor Clutch Circuit Troubleshooting

NOTE:
- Do not use this troubleshooting procedure if the fans are also inoperative. Refer to the symptom troubleshooting index. Symptom Related Diagnostic Procedures
- Before performing symptom troubleshooting, check for powertrain DTCs.

1. Check the No.1 (30 A) fuse in the under-hood fuse/relay box, and the No.14 (10 A) fuse in the under-dash fuse/relay box.

Are the fuses OK ?

YES - Go to step 2.

NO - Replace the fuse(s), and recheck.




2. Check the engine coolant temperature, the throttle position sensor, and the idle speed (use the HDS PGM-FI data list if possible).

Are the engine coolant temperature, throttle position, and idle speed OK?

YES - Go to step 3.

NO - Troubleshoot and repair the cause of the high engine coolant temperature, low idle, or excessively high throttle position sensor reading.

3. Remove the A/C compressor clutch relay from the under-hood fuse/relay box, and test it.

Is the relay OK?

YES - Go to step 4.

NO - Replace the A/C compressor clutch relay.




4. Measure the voltage between the No.2 terminal of the A/C compressor clutch relay 4P socket and body ground.

Is there battery voltage?

YES - Go to step 5.

NO - Replace the under-hood fuse/relay box.




5. Connect the No.1 and No.2 terminals of the A/C compressor clutch relay 4P socket with a jumper wire.

Does the A/C compressor clutch click?

YES - Go to Step 6.

NO - Go to step 14.

6. Disconnect the jumper wire.
7. Turn the ignition switch ON (II).




8. Measure the voltage between the No.3 terminal of the A/C compressor clutch relay 4P socket and body ground.

Is there battery voltage?

YES - Go to step 9.

NO - Repair open in the BLK/YEL wire between the No.14 (10 A) fuse in the under-dash fuse/relay box and the A/C compressor clutch relay.

9. Turn the ignition switch OFF.
10. Reinstall the A/C compressor clutch relay.
11. Make sure the A/C switch is OFF.
12. Turn the ignition switch ON (II).




13. Using a backprobe set, measure the voltage between the No.18 terminal of ECM/PCM connector E (31 ) and body ground with the ECM/PCM connectors connected.

Is there battery voltage?

YES - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/ PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.

NO - Repair open in the wire between the A/C compressor clutch relay and the ECM/PCM.

14. Disconnect the jumper wire.
15. Disconnect the A/C compressor clutch 1P connector.




16. Check for continuity between the No.1 terminal of the A/C compressor clutch relay 4P socket and the No.1 terminal of the A/C compressor clutch 1P connector.

Is there continuity?

YES - Check the A/C compressor clutch clearance, the thermal protector, and the A/C compressor clutch field coil.

NO - Repair open in the wire between the A/C compressor clutch relay and the A/C compressor clutch.