A/C Compressor Clutch Circuit Troubleshooting

HVAC

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, or hard acceleration.
* 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 PGM-FI DTCs Initial Inspection and Diagnostic Overview.

1. Fuses check:

Fuses check
-1. Check the following fuses.





Are the fuses OK?
-YES- Go to step 2.
-NO- Replace the fuse(s). If the fuse(s) blows again, repair a short to ground in the No. A25 (7.5 A) fuse and/or the No. B22 (7.5 A) fuse circuit.

2. Climate control system check:

Climate control system check
-1. Connect the HDS to the DLC.

-2. Start the engine.

-3. Turn on the A/C.

-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 3.
-NO- Troubleshoot the value that is not within the specifications.

3. A/C compressor clutch relay check:

A/C compressor clutch relay check
-1. Turn the ignition switch to LOCK (0).

-2. 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 4.
-NO- Replace the A/C compressor clutch relay.

4. Open wire check (+B_MG_CLUTCH line):

Open wire check (+B_MG_CLUTCH line)
-1. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The +B_MG_CLUTCH wire is OK. Go to step 5.
-NO- Repair an open in the +B_MG_CLUTCH wire.

5. Determine possible failure area (A/C compressor clutch relay switch side circuit, A/C compressor clutch relay coil side circuit):

Determine possible failure area (A/C compressor clutch relay switch side circuit, A/C compressor clutch relay coil side circuit)
-1. Connect terminals 1 and 2 with a jumper wire.









Does the A/C compressor clutch click?
-YES- Go to step 6.
-NO- Go to step 8.

6. Open wire check (IG2_A/C line):

Open wire check (IG2_A/C line)
-1. Disconnect the jumper wire.

-2. Turn the ignition switch to ON (II).

-3. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- The IG2_A/C wire is OK. Go to step 7.
-NO- Repair an open or high resistance in the IG2_A/C wire and A/C compressor clutch relay.

7. Open wire check (A/C_MG_CLUTCH_RLY_CL- line):

Open wire check (A/C_MG_CLUTCH_RLY _CL- line)
-1. Turn the ignition switch to LOCK (0).

-2. Reinstall the A/C compressor clutch relay.

-3. Jump the SCS line with the HDS.
NOTE: This step must be done to protect the PCM from damage.

-4. Disconnect the following connector.





-5. Connect terminals 1 and 2 with a jumper wire.









Does the A/C compressor clutch click?
-YES- Replace the PCM Service and Repair.
-NO- Repair an open in the wire between the A/C compressor clutch relay and the PCM.

8. Open wire check (A/C_MG_CLUTCH/ACC line):

Open wire check (A/C_MG_CLUTCH/ACC line)
-1. Disconnect the jumper wire.

-2. Disconnect the following connector.





-3. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- The A/C_MG_CLUTCH/ACC wire is OK. Check the A/C compressor clutch clearance, and the A/C 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.