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. Reading and Clearing Diagnostic Trouble Codes

1. Check the No. 3-8 (SUB FAN) (30 A) fuse in the under-hood fuse/relay, and the No. 16 (7.5 A) fuse in the driver's under-dash fuse/relay box.

Are you 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. 3-8 (SUB FAN) (30 A) fuse and the No. 16 (7.5 A) fuse circuits.


2. Connect the HDS to the DLC.

3. Turn the ignition switch to ON (II).

4. Turn on the A/C and the blower fan.

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, Reading and Clearing Diagnostic Trouble Codes and retest. 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/Installation from the under-hood fuse/relay box, and test the A/C condenser fan relay. Testing and Inspection

Is the relay OK?
YES - Go to step 8.

NO - Replace the relay circuit board. Under-Hood Fuse/Relay Box Removal/Installation


8. Reinstall the relay circuit board.

9. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the powertrain control module (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, or between the No. 16 (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/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 set the A/C button and fan control button ON.

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/Installation






22. Set the A/C button and fan control button OFF, then turn the ignition switch to LOCK (0).

23. Reconnect the A/C condenser fan motor 2P connector.

24. Connect A/C condenser fan motor 2P connector terminal No. 1 to body ground with a jumper wire.






25. Turn the ignition switch to ON (II), then set the A/C button and fan control button ON.

Does the A/C condenser fan run?
YES - Go to step 26.

NO - Replace the A/C condenser fan motor. Service and Repair


26. Set the A/C button and fan control button OFF, then turn the ignition switch to LOCK (0).

27. Disconnect the jumper wire.

28. Disconnect the under-hood fuse/relay box connector C (5P).

29. Disconnect the A/C condenser fan motor 2P connector.

30. 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 31.

NO - Repair an open in the wire between the under-hood fuse/relay box and the A/C condenser fan motor.






31. Remove the relay circuit board Under-Hood Fuse/Relay Box Removal/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 32.

NO - Replace the relay circuit board. Under-Hood Fuse/Relay Box Removal/Installation


32. Disconnect under-hood fuse/relay box connector B (14P).

33. Disconnect the radiator fan motor 2P connector.

34. 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 35.

NO - Repair an open in the wire between the under-hood fuse/relay box and the radiator fan motor.






35. Check for continuity between radiator fan motor 2P connector terminal No. 1 and body ground.

Is there continuity?
YES - Replace the radiator fan motor. Service and Repair

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.