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Air Conditioning (A/C) Controls

NOTE: The A/C control system information applies to factory installed air conditioning units.

DESCRIPTION
A/C REQUEST SIGNAL: When either the A/C or Defrost mode has been selected and the A/C low and high-pressure switches are closed, an input signal is sent to the Powertrain Control Module (PCM). The PCM uses this input to cycle the A/C compressor through the A/C relay.

If the A/C low or high-pressure switch opens, the PCM will not receive an A/C request signal. The PCM will then remove the ground from the A/C relay. This will deactivate the A/C compressor clutch.