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A/C Signal: Testing and Inspection

CHART C-10 should be used for diagnosing the electrical portion of the A/C compressor clutch circuit. Refer to Chart C-10. Testing and Inspection

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 should have the ability to override the A/C request signal and energize the A/C control relay.