Compressor Clutch Relay: Description and Operation

The A/C compressor control relay cycles the compressor on and off by energizing/de-energizing the compressor clutch coil.

With the key on, 12 volts is applied to the relay common contact and one coil terminal. The second coil terminal is grounded by the PCM when the driver selects A/C or defrost modes, and the pressure cycling switch is closed.

When the relay is energized current passes through the relay contacts which energizes the compressor clutch coil.