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. 3-3 (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 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. 3-3 (SUB FAN) (30 A) fuse in the under-hood fuse/relay, and the No. 16 (7.5 A) fuse circuits.
2. Remove the A/C condenser fan relay from the relay block, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 3.
NO -
Replace the A/C condenser fan relay.
3. Reinstall the A/C condenser fan relay.
4. Connect the HDS to the DLC.
5. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
6. Turn on the A/C.
7. Check the FAN LOW CTRL in the PGM-FI Data List with the HDS.
Is the FAN LOW CTRL on?
YES -
Go to step 8.
NO -
Substitute a known-good ECM/PCM Service and Repair, and retest. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM Service and Repair.
8. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
9. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the ECM/PCM from damage.
10. Disconnect ECM/PCM connector A (49P).
11. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
12. Measure the voltage between ECM/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 ECM/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 and Installation.
13. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
14. Connect the ECM/PCM connector A (49P) terminal No. 4 to body ground with a jumper wire.
15. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
Do the A/C condenser and radiator fans run on low?
YES -
Check for loose wires or poor connections at ECM/PCM connector A (49P) terminal No. 4. If the connections are good, substitute a known-good ECM/PCM, and recheck. If the symptom/indication goes away, replace the original ECM/PCM Service and Repair.
NO -
Go to step 16.
16. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
17. Disconnect the jumper wire.
18. Reconnect ECM/PCM connector A (49P).
19. Disconnect the A/C condenser fan motor 2P connector.
20. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, 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 and Installation.
22. Set the A/C button and fan control button OFF, then turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
23. Test the A/C condenser fan motor Testing and Inspection.
Is the A/C condenser fan 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. 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 C (5P).
26. Disconnect the A/C condenser fan motor 2P connector.
27. Check for continuity between under-hood fuse/relay box connector C (5P) terminal No. 5 and A/C condenser fan motor 2P connector terminal No. 1.
Is there continuity?
YES -
Go to step 28.
NO -
Repair an open in the wire between the under-hood fuse/relay box and the A/C condenser fan motor.
28. Disconnect the radiator fan motor 2P connector.
29. Check for continuity between under-hood fuse/relay box connector C (5P) terminal No. 1 and radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES -
Go to step 30.
NO -
Repair an open in wire between the under-hood fuse/relay box and the radiator fan motor.
30. 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 body ground at G301 Engine Compartment Wire Harness.