Compressor Clutch Relay: Description and Operation

Relay Locations:

PURPOSE

Powertrain Control Module (PCM) monitors engine load and A/C system pressure, and cycles the A/C compressor clutch accordingly.

OPERATION

Relay receives battery voltage from radiator fan relay, (A/C clutch relay will not energize unless the radiator fan relay is energized).

When A/C or defrost is selected, (turned ON), inside vehicle, and low and high pressure switches are closed, PCM receives an A/C ON signal and energizes the relay, by supplying the relay ground.

If PCM senses Wide Open Throttle (WOT) or low idle speed condition, it removes relay ground, discontinueing A/C clutch engagement.