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 powertrain DTCs. Reading and Clearing Diagnostic Trouble Codes

1. Check the No. 3-8 (SUB FAN) (30 A) and No. 21 (7.5 A) 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. 3-8 (SUB FAN) (30 A) fuse and No. 21 (7.5 A) fuse circuits.

2. Connect the HDS to the DLC.

3. Start the engine.

4. Using the HDS, confirm the following values in the PGM-FI Data List at idle.

Are all the values within specifications?
YES - Go to step 5.

NO - Troubleshoot the value that is not within the specifications.

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

6. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.

7. Disconnect PCM connector A (49P).

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

9. Measure the voltage between PCM connector A terminal No. 5 and body ground.

Is there battery voltage?
YES - Go to step 10.

NO - Repair an open in the wire between the under-hood fuse/relay box and the PCM. If the wire is OK, replace the under-hood fuse/relay box. Under-Hood Fuse/Relay Box Removal/Installation

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

11. Connect PCM connector A (49P) terminals No. 4 and No. 5 to body ground with a jumper wire.

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

Does the A/C condenser fan run on high?
YES - Check for loose wires or poor connections at PCM connector A (49P) terminals No. 4 and No. 5. 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

NO - Replace the under-hood fuse/relay box. Under-Hood Fuse/Relay Box Removal/Installation