A/C Compressor Control Circuit

With ignition on, battery voltage is supplied to A/C switch through SR/ACC fuse (10-amp). SR/ACC fuse is located in engine compartment fuse/relay box. With A/C switch on and blower motor switch in any position except OFF, a ground signal is sent through the A/C thermostat contacts to Engine Control Module (ECM) A/C request input.

When ignition switch is on, battery voltage is supplied directly to A/C relay, located in engine compartment fuse/relay box. If predetermined A/C system operating parameters are present, ECM will provide the ground and A/C relay will become energized. When A/C relay is energized, battery voltage is supplied to A/C compressor clutch and condenser fan relay. When A/C condenser fan relay is energized, battery voltage is supplied through CONDENSER FAN fuse (20-amp) located in engine compartment fuse/relay box.