Operation CHARM: Car repair manuals for everyone.

The V5 A/C System

The V5 variable displacement compressor combines with the thermal expansion valve on the evaporator to form a largely self-regulating system. In the high-pressure refrigerant line, there is a pressure sensor rather than a traditional high- or low-pressure cutoff switch, or pressure cycling switch. The compressor clutch is controlled by the powertrain control module (PCM), or the engine control module (ECM), which monitors data from various engine systems. The PCM, or ECM, will disengage the compressor clutch if the following conditions are detected:

- Wide-open throttle.
- High engine coolant temperature.
- High engine rpm.
- Low refrigerant pressure.
- High refrigerant pressure.

The compressor clutch will remain disengaged until normal operation is established.