Operation CHARM: Car repair manuals for everyone.

Non-Trouble Code Procedures

A/C Compressor Clutch Circuit Troubleshooting

NOTE:
- It is normal for the A/C compressor to turn off under certain conditions, such as low idle, high engine coolant temperature, or hard acceleration.
- Do not use this troubleshooting procedure if the fans are also inoperative with the A/C on. Refer to the symptom troubleshooting index. Symptom Related Diagnostic Procedures
- Before performing symptom troubleshooting, check for powertrain DTCs.

1. Check the No. 12 (7.5 A) fuse in the under-hood fuse/relay box, and the No. 30 (7.5 A) fuse in the driver's under-dash fuse/relay box.

Are the fuses OK?

YES - Go to step 2.

NO - Replace the fuse(s), and recheck. If the fuses blow again, check for a short in the No. 12 (7.5 A) and No. 30 (7.5A) fuses circuit.




2. Start the engine, and check the engine coolant temperature and idle speed (use the HDS PGM-FI data list if possible).

Are the coolant temperature and idle speed OK?

YES - Go to step 3.

NO - Troubleshoot and repair the cause of the high engine coolant temperature, or low idle.

3. Turn the ignition switch OFF.
4. 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 5.

NO - Replace the A/C compressor clutch relay.




5. Measure the voltage between the No. 1 terminal of the A/C compressor clutch relay 4P socket and body ground.

Is there battery voltage?

YES - Go to step 6.

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




6. 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 7.

NO - Go to step 15.

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




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

Is there battery voltage?

YES - Go to step 10.

NO - Repair open in the wire between the No. 30 fuse in the driver's under-dash fuse/relay box and the A/C compressor clutch relay.

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




14. Using the backprobe set, measure the voltage between the No. 27 terminal of PCM connector E (31P) and body ground with the PCM connectors connected.

Is there battery voltage?

YES - Check for loose wires or poor connections at PCM connector E (31P). If the connections are good, check the PCM grounds. If the grounds are good, substitute a known-good PCM, and recheck. If the symptom/indication goes away, replace the original PCM.

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

15. Disconnect the jumper wire.
16. Disconnect the A/C compressor clutch 3P connector.




17. Check for continuity between the No. 2 terminal of the A/C compressor clutch relay 4P socket and the No. 1 terminal of the A/C compressor clutch 3P connector.

Is there continuity?

YES - Check the A/C compressor clutch clearance, and the A/C compressor clutch field coil. Repair as needed.

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