Compressor Control Relay
WARNING: This page is about a different car, the 1998 Pontiac Bonneville and 1998 Oldsmobile Eighty-Eight. However, it is still accessible from the selected car via links, so may be relevant.
The compressor control relay cycles the compressor clutch on and off. With ignition on, battery voltage is applied to compressor control relay common contact and one of the compressor clutch contacts. The second compressor clutch contact is grounded by the Powertrain Control Module (PCM). When A/C or defrost mode is selected, the pressure cycling switch is closed, and relay energizes compressor clutch.