A/C Compressor Clutch Circuit Troubleshooting
A/C Compressor Clutch Circuit Troubleshooting
NOTE:
- It is normal for the A/C compressor to turn off under certain conditions, such as low idle, high engine coolant temperature, hard acceleration, or high/low pressure.
- Do not use this troubleshooting procedure if the fans are also inoperative with the A/C on. Refer to the symptom troubleshooting index.
- Before doing any symptom troubleshooting, check for powertrain DTCs Initial Inspection and Diagnostic Overview.
- Check for B-CAN codes. Reading and Clearing Diagnostic Trouble Codes
1. Check the No. 20 (7.5 A) fuse in the under-hood fuse/relay box and the No. 36 (10 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES -
Go to step 2.
NO -
Replace the fuse, and recheck. If the fuse blows again, check for a short in the No. 20 (7.5 A) and No. 36 (10 A) fuses circuit.�
2. Connect the HDS to the DLC.
3. Start the engine.
4. Turn on the A/C.
5. Check the A/C CLUTCH in the PGM-FI Data List with the HDS.
Is the A/C CLUTCH on?
YES -
Go to step 7.
NO -
Go to step 6.
6. 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 7.
NO -
Troubleshoot the value that is not within the specifications.�
7. Remove the A/C compressor clutch relay from the under-hood fuse/relay box, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 8.
NO -
Replace the A/C compressor clutch relay.�
8. Measure the voltage between A/C compressor clutch relay 4P socket terminal No. 1 and body ground.
Is there battery voltage?
YES -
Go to step 9.
NO -
Replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal/Installation.�
9. Connect A/C compressor clutch relay 4P socket terminals No. 1 and No. 2 with a jumper wire.
Does the A/C compressor clutch click?
YES -
Go to step 10.
NO -
Go to step 20.
10. Disconnect the jumper wire.
11. Turn the ignition switch to ON (II).
12. Measure the voltage between A/C compressor clutch relay 4P socket terminal No. 3 and body ground.
Is there battery voltage?
YES -
Go to step 13.
NO -
Repair an open in the wire between the No. 36 (10 A) fuse in the under-dash fuse/relay box and the A/C compressor clutch relay.�
13. Turn the ignition switch to LOCK (0).
14. Reinstall the A/C compressor clutch relay.
15. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.
16. Disconnect PCM connector A (44P) ('07-09 models) or A (49P) ('10-11 models).
17. '07-09 models: Connect PCM connector A (44P) terminal No. 14 to body ground with a jumper wire.
18. '10-11 models: Connect PCM connector A (49P) terminal No. 15 to body ground with a jumper wire.
19. Turn the ignition switch to ON (II).
Does the A/C compressor click?
YES -
Check for loose wires or poor connections at PCM connector A (44P) ('07-09 models) PCM connector A (49P) ('10-11 models). If the connections are good, check the PCM grounds. If the grounds are good, substitute a known-good PCM, '07-09 models Initial Inspection and Diagnostic Overview, '10-11 models, and recheck. If the symptom/indication goes away, replace the original PCM, '07-09 models Service and Repair, '10-11 models Service and Repair.�
NO -
Repair an open in the wire between the A/C compressor clutch relay and the PCM.�
20. Disconnect the jumper wire.
21. Disconnect the A/C compressor clutch 3P connector.
22. Check for continuity between A/C compressor clutch relay 4P socket terminal No. 2 and A/C compressor clutch 3P connector terminal No. 3.
Is there continuity?
YES -
Check the A/C compressor clutch clearance, and the compressor clutch field coil Testing and Inspection. Repair as needed.�
NO -
Repair an open in the wire between the A/C compressor clutch relay and the A/C compressor clutch.�