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 doing symptom troubleshooting, check for PGM-FI DTCs Initial Inspection and Diagnostic Overview.
1. Check the No. 3-8 (SUB FAN MTR) (30 A) fuse in the under-hood fuse/relay.
Is the fuse OK?
YES -
Go to step 2.
NO -
Replace the fuse, and recheck. If the fuse blow again, check for a short in the No. 3-8 (SUB FAN MTR) (30 A) fuse circuit.�
2. Connect the HDS to the DLC.
3. Turn the ignition switch to ON (II).
4. Turn on the A/C.
5. Check the FAN LOW CTRL in the PGM-FI Data List with the HDS.
Is the FAN LOW CTRL on?
YES -
Go to step 6.
NO -
Substitute a known-good PCM, and recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.�
6. Turn the ignition switch to LOCK (0).
7. Remove the relay circuit board Under-Hood Fuse/Relay Box Removal and Installation from the under-hood fuse/relay box, and test the A/C condenser fan relay and the fan control relay Testing and Inspection.
Are the relays OK?
YES -
Go to step 8.
NO -
Replace the relay circuit board.�
8. Reinstall the relay circuit board.
9. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the PCM from damage.
10. Disconnect PCM connector A (49P).
11. Turn the ignition switch to ON (II).
12. Measure the voltage between PCM connector A terminal No. 4 and body ground.
Is there battery voltage?
YES -
Go to step 13.
NO -
Repair an open in the wires between the under-hood fuse/relay box and the PCM. If the wires are OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.�
13. Turn the ignition switch to LOCK (0).
14. Connect PCM connector A (49P) terminal No. 4 to body ground with a jumper wire.
15. Turn the ignition switch to ON (II).
Do the A/C condenser and radiator fans run on low?
YES -
Check for loose wires or poor connections at PCM connector A (49P) terminal No. 4. If the connections are good, substitute a known-good PCM, and recheck. If the symptom/indication goes away, replace the original PCM Service and Repair.�
NO -
Go to step 16.
16. Turn the ignition switch to LOCK (0).
17. Disconnect the jumper wire.
18. Reconnect PCM connector A (49P).
19. Disconnect the A/C condenser fan motor 2P connector.
20. Turn the ignition switch to ON (II), then turn on the A/C.
21. 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 22.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the A/C condenser fan motor. If the wire is OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.�
22. Turn off the A/C, then turn the ignition switch to LOCK (0).
23. Test the A/C condenser fan motor Testing and Inspection.
Is the motor OK?
YES -
Go to step 24.
NO -
Replace the A/C condenser fan motor Radiator and A/C Condenser Fan, Motor, and Shroud Removal and Installation.�
24. Disconnect the under-hood fuse/relay box connector C (5P).
25. Check for continuity between under-hood fuse/relay box connector C (5P) terminal No. 3 and A/C condenser fan motor 2P connector terminal No. 1.
Is there continuity?
YES -
Go to step 26.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the A/C condenser fan motor.�
26. Disconnect under-hood fuse/relay box connector B (14P).
27. Disconnect the radiator fan motor 2P connector.
28. Check for continuity between under-hood fuse/relay box connector B (14P) terminal No. 2 and radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES -
Go to step 29.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the radiator fan motor.�
29. Check for continuity between radiator fan motor 2P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Replace the radiator fan motor Radiator and A/C Condenser Fan, Motor, and Shroud Removal and Installation.�
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.�