A/C Signal: Testing and Inspection

HVAC Compressor Control Chart should be used for diagnosing the electrical portion of the A/C compressor clutch circuit.

A scan tool will be used in diagnosing the system. The scan tool has the ability to read the A/C request and refrigerant pressure inputs to the PCM. The scan tool can display when the PCM has commanded the A/C clutch ON. The scan tool has the ability to override the A/C request signal and energize the A/C control relay.