Non-Trouble Code Procedures
Compressor Clutch Circuit TroubleshootingNOTE: Do not use this troubleshooting procedure if the fans are also inoperative, refer to the symptom troubleshooting index.
1. Check the No.9 (20 A) fuse in the under-hood fuse/relay box, and the No.30 (7.5 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, throttle position, and idle speed (use the HDS PGM-FI data list if possible).
Is the 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 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 compressor clutch relay.
4. Measure the voltage between the No.1 terminal of the 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 compressor clutch relay 4P socket with a jumper wire.
Does the 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.4 terminal of the 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.30 fuse in the under-dash fuse/relay box and the compressor clutch relay.
9. Turn the ignition switch OFF.
10. Reinstall the 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 (31P) and body ground with the ECM/PCM connectors connected.
Is there battery voltage?
YES - Check for loose wires or poor connections at terminal E18 of the ECM/PCM connector E (31P). If the connections are good, substitute a known-good ECM/PCM, and recheck. If the symptom/indication goes away, replace the original ECM/PCM.
NO - Repair open in the wire between the compressor clutch relay and the ECM/PCM.
14. Disconnect the jumper wire.
15. Disconnect the compressor clutch 3P connector.
16. Check for continuity between the No.2 terminal of the compressor clutch relay 4P socket and the No.2 terminal of the compressor clutch 3P connector.
Is there continuity?
YES - Check the compressor clutch clearance, and the compressor clutch field coil. Repair as needed.
NO - Repair open in the wire between the compressor clutch relay and the compressor clutch.