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A/C Signal: Description and Operation

A/C Relay/WAC Relay:





The [1][2][3]A/C Relay (ACR) is controlled by the Powertrain Control Module (PCM) with an output signal. The signal acts as a circuit ON/OFF switch for the compressor magnetic clutch. The PCM will cut off the ACR during Wide Open Throttle (WOT) conditions, thus the relay is sometimes referred to as the Wide Open Throttle Air Conditioning Cutoff (WAC) relay.