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A/C Signal: Testing and Inspection

Refer to System Diagnosis / C-charts Component Testing / Chart C-10B for diagnosing the electrical portion of the A/C circuit. Chart C-10B A/C Clutch Control Circuit Diagnosis

The Heating and Air Conditioning Section should be used for diagnosing the refrigerant portion of the system.

The "Scan" tool will be used in diagnosing the system, as it has the ability to read the A/C request input to the Electronic Control Module (ECM), as well as displaying when the ECM has commanded the A/C clutch "ON."