Radiator and A/C Condenser Fan Low Speed Circuit Troubleshooting
Radiator and A/C Condenser Fan Low Speed Circuit TroubleshootingNOTE:
- Do not use this troubleshooting procedure if the compressor is inoperative. Refer to the symptom troubleshooting index. Heating/Air Conditioning
- Before performing symptom troubleshooting, check for powertrain DTCs.
1. Check the No. 58 (30 A) fuse in the under-hood fuse/relay box, and the No. 3 (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.
2. Remove the A/C 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 A/C condenser fan relay.
3. Measure the voltage between the No. 1 terminal of the A/C 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 A/C condenser fan relay 4P socket with a jumper wire.
Does the A/C condenser fan run?
YES - Go to step 5.
NO - Go to step 13.
5. Disconnect the jumper wire.
6. Turn the ignition switch ON (II).
7. Measure the voltage between the No. 3 terminal of the A/C condenser fan relay 4P socket and body ground.
Is there battery voltage?
YES - Go to step 8.
NO - Go to step 31.
8. Turn the ignition switch OFF.
9. Reinstall the A/C condenser fan relay.
10. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.
11. Disconnect PCM connector A (44P), and turn the ignition switch ON (II).
12. Measure the voltage between the No. 4 terminal of PCM connector A (44P) and body ground.
Is there battery voltage?
YES - Check for loose wires or poor connections at No. 4 terminal of PCM connector A (44P). If the connections 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 condenser fan relay and the PCM.
13. Disconnect the jumper wire.
14. Reinstall the A/C condenser fan relay.
15. Disconnect the A/C condenser fan 2P connector.
16. Turn the ignition switch ON (II), then turn the A/C and blower fan switches ON.
17. Measure the voltage between the No. 2 terminal of the A/C condenser fan 2P connector and body ground.
Is there battery voltage?
YES - Go to step 18.
NO - Repair open in the wire between the A/C condenser fan relay and the A/C condenser fan.
18. Turn the A/C and fan switches OFF, then turn the ignition switch OFF.
19. Reconnect the A/C condenser fan 2P connector.
20. Connect the No. 1 terminal of the A/C condenser fan 2P connector to body ground with a jumper wire.
21. Turn the ignition switch ON (II), then turn the A/C and fan switches ON.
Does the A/C condenser fan run?
YES - Go to step 22.
NO - Replace the A/C condenser fan motor.
22. Turn the A/C and fan switches OFF, then turn the ignition switch OFF.
23. Disconnect the jumper wire.
24. Remove the fan control relay from the auxiliary under-hood relay box, and test it.
Is the relay OK?
YES - Go to step 25.
NO - Replace the fan control relay.
25. Turn the ignition switch ON (II), then turn the A/C and fan switches ON.
26. 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 27.
NO - Repair open in the wire between the A/C condenser fan and the fan control relay.
27. Turn the A/C and fan switches OFF, then turn the ignition switch OFF.
28. Disconnect the radiator fan 2P connector.
29. Check for continuity between the No. 4 terminal of the fan control relay 5P socket and the No. 2 terminal of the radiator fan 2P connector.
Is there continuity?
YES - Go to step 30.
NO - Repair open in the wire between the radiator fan relay and the radiator fan.
30. 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 G202.
31. Remove A/C diode A from under the dashboard.
32. 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 33.
NO - Replace A/C diode A.
33. Turn the ignition switch ON (II).
34. Measure the voltage between the No. 4 terminal of A/C diode 4P connector and body ground.
Is there battery voltage?
YES - Repair open in the wire between A/C diode 4P connector terminal No. 3 and the A/C condenser fan relay.
NO - Repair open in the wire between the No. 3 (7.5 A) fuse in the driver's under-dash fuse/relay box and A/C diode 4P connector terminal No. 4.