Compressor Clutch Relay: Description and Operation

A/C Fan And Clutch Relay Locations:

Purpose

Supplies ground path for A/C compressor clutch.

Operation

Controlled by A/C or defrost switch (inside vehicle) and Powertrain Control Module (PCM). Relay receives battery voltage from radiator fan relay, (A/C 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. PCM then supplies relay ground.

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

PCM delays activation of A/C relay for a specific period after engine start-up.