Compressor Clutch Circuit Troubleshooting
Compressor Clutch Circuit Troubleshooting1. Check the No.1 (20 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 Honda PGM Tester PGM-FI data list if possible).
Is the coolant temperature above normal, the throttle position sensor reading too high, or the idle speed too low?
YES - Troubleshoot and repair the cause of the high engine coolant temperature, high throttle position sensor reading, or low idle speed.
NO - Go to step 3.
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.2 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.3 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 wire between the No.14 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 the Backprobe Set, measure the voltage between the No.18 terminal of ECM connector E (31P) and body ground with the ECM connectors connected.
Is there battery voltage ?
YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Repair open in the wire between the compressor clutch relay and the ECM.
14. Disconnect the jumper wire.
15. Disconnect the compressor clutch 1P connector.
16. Check for continuity between the No.1 terminal of the compressor clutch relay 4P socket and the No.1 terminal of the compressor clutch 1P connector.
Is there continuity ?
YES - Check the compressor clutch clearance, the thermal protector, and the compressor clutch field coil.
NO - Repair open in the wire between the compressor clutch relay and the compressor clutch.