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 powertrain DTCs Initial Inspection and Diagnostic Overview.
1. Check the No. 30 (30 A) and the No. 10 (7.5 A) fuses in the 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. 30 (30 A) and No. 10 (7.5 A) fuses circuit.�
2. Remove the radiator fan relay from the auxiliary under-hood relay box, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 3.
NO -
Replace the radiator fan relay.�
3. Connect the HDS to the DLC.
4. Turn the ignition switch to ON (II).
5. Turn the A/C and FAN to ON on the climate control unit.
6. Check the FAN LOW CTRL in the PGM-FI Data List with the HDS.
Is the FAN LOW CTRL on?
YES -
Go to step 7.
NO -
Substitute a known-good PCM, and retest. If the symptom/indication goes away with a known-good PCM, replace the original PCM Service and Repair.�
7. Measure the voltage between radiator fan relay 4P socket terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 8.
NO -
Repair an open in the wire between the No. 30 (30 A) fuse in the under-dash fuse/relay box and the radiator fan relay.�
8. Connect radiator fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire.
Do the radiator and A/C condenser fans run?
YES -
Go to step 9.
NO -
Go to step 18.
9. Disconnect the jumper wire.
10. Turn the ignition switch to ON (II).
11. Measure the voltage between radiator fan relay 4P socket terminal No. 4 and body ground.
Is there battery voltage?
YES -
Go to step 12.
NO -
Repair an open in the wire between the No. 10 (7.5 A) fuse in the under-dash fuse/relay box, A/C diode A and the radiator fan relay.�
12. Turn the ignition switch to LOCK (0).
13. Reinstall the radiator fan relay.
14. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.
15. Disconnect PCM connector A (44P).
16. Connect PCM connector A (44P) terminal No. 4 to body ground with a jumper wire.
17. Turn the ignition switch to ON (II).
Do the radiator and A/C condenser fans run on low?
YES -
Check for loose wires or poor connections at 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 Service and Repair, then do the PCM idle learn procedure PCM Idle Learn Procedure.�
NO -
Repair an open in the wire between the radiator fan relay and the PCM.�
18. Disconnect the jumper wire.
19. Reinstall the radiator fan relay.
20. Disconnect the radiator fan motor 2P connector.
21. Turn the ignition switch to ON (II), then turn the A/C switch and fan control switch ON.
22. Measure the voltage between radiator fan motor 2P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 23.
NO -
Repair an open in the wire between the radiator fan relay and the radiator fan motor.�
23. Turn the A/C switch and fan control switch OFF, then turn the ignition switch to LOCK (0).
24. Test the radiator fan motor Testing and Inspection.
Is the motor OK?
YES -
Go to step 25.
NO -
Replace the radiator fan motor Radiator And A/C Condenser Fan, Motor, And Shroud Removal And Installation.�
25. Remove the fan control relay from the auxiliary under-hood fuse/relay box, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 26.
NO -
Replace the fan control relay.�
26. Turn the ignition switch ON (II), then turn the A/C switch and fan control switch ON.
27. Measure the voltage between fan control relay 5P socket terminal No. 1 and body ground.
Is there battery voltage?
YES -
Go to step 28.
NO -
Repair an open in the wire between the radiator fan motor and the fan control relay.�
28. Turn the A/C switch and fan control switch OFF, then turn the ignition switch to LOCK (0).
29. Disconnect the A/C condenser fan motor 2P connector.
30. Check for continuity between fan control relay 5P socket terminal No. 4 and A/C condenser fan motor 2P connector terminal No. 2.
Is there continuity?
YES -
Go to step 31.
NO -
Repair an open in the wire between the fan control relay and the A/C condenser motor fan.�
31. Check for continuity between A/C condenser fan motor 2P connector terminal No. 1 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 and body ground. If the wire is OK, check for poor ground at G401.�