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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 the A/C compressor is inoperative. Refer to the symptom troubleshooting index. Symptom Related Diagnostic Procedures

1. Check the No. 1 (30 A) and No. 4 (20 A) fuses in the under-hood fuse/relay box, and the No. 14 (10 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.

Is there battery voltage?

YES - Go to step 5.

NO - Repair open in the BLK/YEL wire between the No. 14 (10 A) fuse in the under-dash fuse/relay box and the radiator fan relay socket, and the A/C condenser fan relay socket.

5. Turn the ignition switch OFF.
6. Reinstall the A/C condenser fan relay.
7. Make sure the A/C switch is OFF.
8. Turn the ignition switch ON (II).




9. Using the 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 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 socket, the A/C condenser fan relay socket and the ECM/PCM.