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V5 A/C System Description

V5 A/C System Description

The V5 variable displacement compressor along with the thermal expansion valve on the evaporator, constitutes a largely self-regulating system. There is no pressure cycling switch, no high-pressure cut-off switch and no low-pressure cut-off switch. The compressor clutch is controlled by the electronic control module (ECM), which receives data from various engine systems and from a pressure transducer located in the high-pressure refrigerant pipe. In normal operation, the clutch is engaged continuously. Should one of the monitored conditions become abnormal, the ECM will disengage the compressor clutch until normal operation is restored. These conditions include the following:
^ Wide-open throttle.
^ High engine coolant temperature.
^ High engine RPM.
^ Refrigerant low pressure.
^ Refrigerant high pressure.

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