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. Symptom Related Diagnostic Procedures
- Before doing symptom troubleshooting, check for PGM-FI DTCs Initial Inspection and Diagnostic Overview.
1. Check the No. A3-6 (MAIN FAN) (30 A) fuse in the under-hood fuse/relay box, and the No. B16 (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. If the fuse(s) blow again, check for a short in the No. A3-6 (MAIN FAN) (30 A) fuse and/or the No. B16 (7.5 A) fuse circuit(s).
2. Connect the HDS to the DLC How to Troubleshoot the Climate Control System.
3. Start the engine.
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. Set the air conditioning button and fun control dial to off, then turn the ignition switch to LOCK (0).
7. Remove the radiator fan relay from the under-hood fuse/relay box, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 8.
NO -
Replace the radiator fan relay.
8. Reinstall the radiator fan relay.
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 (49P) terminal No. 44 and body ground.
Is there battery voltage?
YES -
Go to step 13.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the PCM, or between the No. B16 (7.5 A) fuse in driver's under-dash fuse/relay box and the under-hood fuse/relay box. If 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. 44 to body ground with a jumper wire.
15. Turn the ignition switch to ON (II).
Do the A/C condenser and the radiator fans run on low?
YES -
Check for loose wires or poor connections at PCM connector A (49P). 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 radiator fan motor 2P connector.
20. Turn the ignition switch to ON (II), then turn on the A/C.
21. Measure the voltage between radiator fan motor 2P connector terminal No. 1 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 radiator fan motor. If the wire is OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.
22. Turn the ignition switch to LOCK (0).
23. Test the radiator fan motor Testing and Inspection.
Is the radiator fan motor OK?
YES -
Go to step 24.
NO -
Replace the radiator fan motor Radiator And A/C Condenser Fan, Motor, And Shroud Removal And Installation.
24. Remove the relay circuit board Under-Hood Fuse/Relay Box Removal and Installation, from the under-hood fuse/relay box, and test the fan control relay Testing and Inspection.
Is the relay OK?
YES -
Go to step 25.
NO -
Replace the relay circuit board.
25. Disconnect under-hood fuse/relay box connector B (14P).
26. Check for continuity between under-hood fuse/relay box connector B (14P) terminal No. 10 and radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES -
Go to step 27.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the radiator fan motor.
27. Disconnect under-hood fuse/relay box connector D (10P).
28. Disconnect the A/C condenser fan motor 2P connector.
29. Check for continuity between under-hood fuse/relay box connector D (10P) terminal No. 1 and A/C condenser fan motor 2P connector terminal No. 1.
Is there continuity?
YES -
Go to step 30.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the A/C condenser fan motor.
30. Check for continuity between A/C condenser fan motor 2P connector terminal No. 2 and body ground.
Is there continuity?
YES -
Replace the A/C condenser fan motor Radiator And A/C Condenser Fan, Motor, And Shroud Removal And Installation.
NO -
Check for an open in the wire between the A/C condenser fan motor and body ground. If the wire is OK, check for poor ground at G301.