Radiator and A/C Condenser Fan Common Circuit Troubleshooting

Radiator and A/C Condenser Fan Common Circuit Troubleshooting

NOTE: Do not use this troubleshooting procedure if only one fan is inoperative, or if the A/C compressor is inoperative, refer to the symptom troubleshooting index Symptom Related Diagnostic Procedures

1. Check the No. 9 (20 A) and No. 11 (20 A) fuses in the under-hood fuse/relay box, and the No. 30 (7.5 A) fuse in the under-dash fuse/relay box.

Are the fuses OK?

YES - Go to step 2.

NO - Replace the fuse(s), and recheck.

2. Remove the A/C condenser fan relay from the under-hood fuse/relay box.
3. Turn the ignition switch ON (II).




4. Measure the voltage between the No. 3 terminal of the A/C condenser fan relay 4P socket and body ground.

YES - Go to step 5.

NO - Repair open in the BLK/YEL wire between the No. 30 fuse in the under-dash fuse/relay box and the A/C condenser fan relay.

5. Turn the ignition switch OFF.
6. Reinstall the A/C condenser fan relay.
7. Make sure the A/C switch is OFF, and the engine coolant temperature is below 199 degrees F (93 degrees C).
8. Turn the ignition switch ON (II).




9. Using a backprobe set, measure the voltage between the No. 12 terminal of ECM/PCM connector E (31P) and body ground with the ECM/PCM connectors connected.

Is there battery voltage?

YES - Check for loose wires or poor connections at terminal E12 of the ECM/PCM connector E (31P). If the connections are good, substitute a known-good ECM/PCM, and recheck. If the symptom/indication goes away, replace the original ECM/PCM.

NO - Repair open in the wire between the radiator fan relay, the A/C condenser fan relay, and the ECM/PCM.

NOTE: After replacing the ECM/PCM, do the following items:
- ECM/PCM idle learn procedure.
- Enter the anti-theft codes for the radio and navigation system, then enter the customer's radio station presets.
- Replace ECM/PCM procedure with HDS.