Radiator and A/C Condenser Fan Low Speed Circuit Troubleshooting
Radiator and A/C Condenser Fan Low Speed Circuit Troubleshooting
NOTE:
- Do not use this troubleshooting procedure if the A/C compressor is inoperative. Refer to the symptom troubleshooting index.
- Before performing symptom troubleshooting, check for powertrain DTCs Initial Inspection and Diagnostic Overview.
1. Check the No. 9 (30 A) fuse in the under-hood fuse/relay box, and the No. 30 (10 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 Power Relay Test.
Is the relay OK?
YES -
Go to step 3.
NO -
Replace the A/C condenser fan relay.�
3. Measure the voltage between A/C condenser fan relay 4P socket terminal No. 1 and body ground.
Is there battery voltage?
YES -
Go to step 4.
NO -
Replace the under-hood fuse/relay box.�
4. Connect A/C condenser fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire.
Do the A/C condenser and radiator fans run?
YES -
Go to step 5.
NO -
Go to step 14.
5. Disconnect the jumper wire.
6. Turn the ignition switch to ON (II).
7. Measure the voltage between A/C condenser fan relay 4P socket terminal No. 3 and body ground.
Is there battery voltage?
YES -
Go to step 8.
NO -
Go to step 34.
8. Turn the ignition switch to LOCK (0).
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 (49P).
12. Connect PCM connector A (49P) terminal No. 4 to body ground with a jumper wire.
13. Turn the ignition switch to ON (II).
Does the A/C condenser and radiator fans run?
YES -
Check for loose wires or poor connections at PCM connector A (49P). 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 Service and Repair.�
NO -
Repair an open in the wire between the A/C condenser fan relay and the PCM.�
14. Disconnect the jumper wire.
15. Reinstall the A/C condenser fan relay.
16. Disconnect the A/C condenser fan motor 2P connector.
17. Turn the ignition switch to ON (II), then set the A/C button and fan control dial ON.
18. Measure the voltage between A/C condenser fan motor 2P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 19.
NO -
Repair an open in the wire between the A/C condenser fan relay and the A/C condenser fan motor.�
19. Set the A/C button and fan control dial OFF, then turn the ignition switch to LOCK (0).
20. Reconnect the A/C condenser fan motor 2P connector.
21. Connect A/C condenser fan motor 2P connector terminal No. 1 to body ground with a jumper wire.
22. Turn the ignition switch to ON (II), then set the A/C button and fan control dial ON.
Does the A/C condenser fan run?
YES -
Go to step 23.
NO -
Replace the A/C condenser fan motor.�
23. Set the A/C button and fan control dial OFF, then turn the ignition switch to LOCK (0).
24. Disconnect the jumper wire.
25. Remove the fan control relay from the auxiliary under-hood relay box, and test it Power Relay Test.
Is the relay OK?
YES -
Go to step 26.
NO -
Replace the fan control relay.�
26. Connect fan control relay 5P socket terminal No. 1 to body ground with a jumper wire.
27. Turn the ignition switch to ON (II), then set the A/C button and fan control dial ON.
Does the A/C condenser fan run?
YES -
Go to step 28.
NO -
Repair an open in the wire between the A/C condenser fan motor and the fan control relay.�
28. Set the A/C button and fan control dial OFF, then turn the ignition switch to LOCK (0).
29. Remove the radiator fan relay from the under-hood fuse/relay box.
30. Check for continuity between fan control relay 5P socket terminal No. 4 and radiator fan relay 4P socket terminal No. 1.
Is there continuity?
YES -
Go to step 31.
NO -
Repair an open in the wire between the fan control relay and the radiator fan relay.�
31. Disconnect the radiator fan motor 2P connector.
32. Check for continuity between radiator fan relay 4P socket terminal No. 1 and radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES -
Go to step 33.
NO -
Repair an open in the wire between the radiator fan relay and the radiator fan motor.�
33. Check for continuity between radiator fan motor 2P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Replace the radiator fan motor.�
NO -
Check for an open in the wire between the radiator fan motor and body ground. If the wire is OK, check for poor ground at G301.�
34. Turn the ignition switch to LOCK (0).
35. Remove A/C diode A from under-hood fuse/relay box.
36. Using the diode setting () on a DVOM, check for current flow in both directions between A/C diode A terminals No. 1 and No. 2.
Is there current flow in only one direction?
YES -
Go to step 37.
NO -
Replace A/C diode A.�
37. Turn the ignition switch to ON (II).
38. Measure the voltage between A/C diode A 2P socket terminal No. 2 and body ground.
Is there battery voltage?
YES -
Open in the wire between the A/C diode A 2P socket terminal No. 1 and A/C condenser fan relay.�
NO -
Repair an open in the wire between the No. 30 (10 A) fuse in the driver's under-dash fuse/relay box and A/C diode A pin 2.�