Compressor Clutch Does Not Engage

HVAC Compressor Clutch Does Not Engage

Diagnostic Aids

Refer to the following table for reference of air conditioning (A/C) refrigerant high side pressure sensor signal reading conversion from the DMM voltage value to psi value.






Test Description

Step 1 - Step 7:

Step 8 - Step 18:

Step 19 - Step 31:

Step 32 - Step 39:

The numbers below refer to the step numbers on the diagnostic table.
2. The A/C compressor relay output is disabled if engine coolant temperature is above 128°C (262°F). The instrument panel engine coolant indicator will indicate overheating.
3. Place the mode switch in any position except OFF, and place the air temperature control switch in a cold setting. Use the bi-level mode for consistent testing of the A/C system operation.
6. The HVAC control module is inoperative if the module does not respond to any operator control requests.