Radiator and Condenser Fans Low Speed Circuit Troubleshooting
Radiator and Condenser Fan Low Speed Circuit TroubleshootingNOTE:
- Do not use this troubleshooting procedure if the compressor' is inoperative. Refer to the symptom troubleshooting index.
- Before performing symptom troubleshooting, check for powertrain DTCs.
1. Check the No.9 (30 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. Remove the condenser fan relay from the under- hood fuse/relay box, and test it.
Is the relay OK?
YES - Go to step 3.
NO - Replace the condenser fan relay.
3. Measure the voltage between the No.1 terminal of the condenser fan relay 4P socket and body ground.
Is there battery voltage?
YES - Go to step 4.
NO - Replace the under-hood fuse/relay box.
4. Connect the No.1 and No.2 terminals of the condenser fan relay 4P socket with a jumper wire.
Does the condenser fan run?
YES - Go to step 5.
NO - Go to step 12.
5. Disconnect the jumper wire.
6. Turn the ignition switch ON (II).
7. Measure the voltage between the No.3 terminal of the condenser fan relay 4P socket and body ground.
Is there battery voltage?
YES - Go to step 8.
NO - Go to step 32.
8. Turn the ignition switch OFF.
9. Reinstall the condenser fan relay.
10. Turn the ignition switch ON (II).
11. Using the backprobe set, measure the voltage between the No.6 terminal of ECM/PCM connector A (31P) and body ground with the ECM/PCM connectors connected.
Is there battery voltage?
YES - Check for loose wires or poor connections at No.6 terminal of the ECM/PCM connector A (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, then perform the ECM/PCM idle learn procedure.
NO - Repair open in the wire between the condenser fan relay and the ECM/PCM.
12. Disconnect the jumper wire.
13. Reinstall the condenser fan relay.
14. Disconnect the condenser fan 2P connector.
15. Turn the ignition switch ON (II), then turn the A/C and blower fan switches ON.
16. Measure the voltage between the No.2 terminal of the condenser fan 2P connector and body ground.
Is there battery voltage?
YES - Go to step 17.
NO - Repair open in the wire between the condenser fan relay and the condenser fan.
17. Turn the A/C and fan switches OFF, then turn the ignition switch OFF.
18. Reconnect the condenser fan 2P connector.
19. Connect the No.1 terminal of the condenser fan 2P connector to body ground with a jumper wire.
20. Turn the ignition switch ON (II), then turn the A/C and fan switches ON.
Does the condenser fan run?
YES - Go to step 21.
NO - Replace the condenser fan motor.
21. Turn the A/C and fan switches OFF, then turn the ignition switch OFF.
22. Disconnect the jumper wire.
23. Remove the fan control relay from the multi-relay box, and test it
Is the relay OK?
YES - Go to step 24.
NO - Replace the fan control relay.
24. Turn the ignition switch ON (II), then turn the A/C and fan switches ON.
25. Measure the voltage between the No.1 terminal of the fan control relay 5P socket and body ground.
Is there battery voltage?
YES - Go to step 26.
NO - Repair open in the wire between the condenser fan and the fan control relay.
26. Turn the A/C and fan switches OFF, then turn the ignition switch OFF.
27. Remove the radiator fan relay from the under-hood fuse/relay box.
28. Check for continuity between the No.4 terminal of the fan control relay 5P socket and the No.1 terminal of the radiator fan relay 4P socket.
Is there continuity?
YES - Go to step 29.
NO - Repair open in the wire between the fan control relay and the radiator fan relay.
29. Disconnect the radiator fan 2P connector.
30. Check for continuity between the No.1 terminal of the radiator fan relay 4P socket and the No 2 terminal of the radiator fan 2P connector.
Is there continuity?
YES - Go to step 31.
NO - Repair open in the wire between the radiator fan relay and the radiator fan.
31. Check for continuity between the No.1 terminal of the radiator fan 2P connector and body ground.
Is there continuity?
YES - Replace the radiator fan motor.
NO - Check for an open in the wire between the radiator fan and body ground. If the wire is OK check for poor ground at G301.
32. Remove A/C diode A from under the dashboard.
33. Using the diode setting (--|<--) on a DVOM, check for current flow in both directions between the No. 1 and No.2 terminals of A/C diode A.
Is there current flow in only one direction?
YES - Go to step 34.
NO - Replace A/C diode A.
34. Turn the ignition switch ON (II).
35. Measure the voltage between the No.2 terminal of A/C diode A 2P socket and body ground.
Is there battery voltage?
YES - Repair open in the wire between A/C diode A pin land the condenser fan relay.
NO - Repair open in the wire between the No.30 fuse in the under-dash fuse/relay box and A/C diode A pin 2.