Chart 1 No Compressor Operation

CIRCUIT DESCRIPTION

The compressor clutch coil is fed power through the A/C relay and is grounded through the A/C ground (CKT 150).

TEST DESCRIPTION

Numbers below refer to circled numbers on the diagnostic chart.

1. This step checks continuity of the compressor clutch relay circuitry.

2. This step checks to see whether the compressor clutch can be controlled by the ECM or not.

3. This step checks to see if the compressor clutch relay is receiving power.

4. This step checks to see if the ECM has disabled the compressor because of a faulty power steering pressure switch input.

5. This step bypasses the compressor clutch relay to engage the compressor.

6. This step checks to see if the compressor clutch relay is receiving power on CKT 257.

7. This step checks for a short to voltage on CKT 900.

8. This step checks to see if the compressor clutch relay is receiving power on CKT 258.

9. This step checks to see if there is an open in the feed or ground side of the compressor clutch relay drive.