Diagnostic Aids

WARNING: This page is about a different car, the 2016 GMC Acadia, 2016 Chevrolet Traverse, and 2016 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.

The following conditions must be met in order for the ECM to turn on the compressor clutch:

Battery voltage is between 9-18 volts.
Engine coolant temperature (ECT) is less than 123°C (253°F).
Engine speed is greater than 600 RPM.
Engine speed is less than 4, 760 RPM.
A/C high side pressure is between 269-2929 kPa (39-425 psi)-Refer to Air Conditioning (A/C) System Performance Test .
Throttle position is less than 100 percent.
Evaporator temperature is greater than 0°C (32°F).
ECM does not detect excessive torque load.
ECM does not detect insufficient idle quality.
The ambient temperature is above 1°C (34°F).