A/C Condenser Fan High Speed Circuit Troubleshooting

A/C Condenser Fan High 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 any symptom troubleshooting, check for PGM-FI DTCs How to Troubleshoot the Fuel and Emissions Systems.

1. Check the No. 5 (20 A) fuse and the No. 21 (7.5 A) fuse in the under-hood fuse/relay box.

Are the fuses OK?

YES -

Go to step 2.

NO -

Replace the fuse(s), and recheck. If fuse(s) blow again, check for a short in the No. 5 (20 A) fuse and/or the No. 21 (7.5 A) fuse circuit(s).

2. Remove the relay circuit board Under-Hood Fuse/Relay Box Removal and Installation from the under-hood fuse/relay box, and test the A/C condenser fan relay and the fan control relay Testing and Inspection.

Are the relays OK?

YES -

Go to step 3.

NO -

Replace the relay circuit board.

3. Reinstall the relay circuit board.

4. Jump the SCS line with the HDS.

NOTE: This step must be done to protect the ECM/PCM from damage.

5. Disconnect ECM/PCM connector A (49P).

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

7. Measure the voltage between ECM/PCM connector A (49P) terminal No. 6 and body ground.





Is there battery voltage?

YES -

Go to step 8.

NO -

Repair an open in the wire between the under-hood fuse/relay box and the ECM/PCM. If the wire is OK, replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.

8. Turn the ignition switch to LOCK (0).

9. Connect ECM/PCM connector A (49P) terminals No. 5, No. 6, and No. 22 to body ground with jumper wires.






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

Do the A/C condenser and radiator fans run on high?

YES -

Check for loose wires or poor connections at ECM/PCM connector A (49P). 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 -

Check for an open in the wire between the under-hood fuse/relay box and body ground. If the wire is OK, check for poor ground at G301.