A/C Compressor Control Circuit
When ignition is turned on, battery voltage is applied to A/C relay and A/C cut relay. The A/C cut relay and A/C relay are located behind glove box, in passenger compartment. When A/C switch and blower motor switch are turned on, ground is supplied to A/C relay which energizes A/C relay. When A/C relay is energized, battery voltage is supplied to A/C condenser fan motor through ADD fuse (30-amp), located in engine compartment fuse/relay box.
When A/C relay is energized, a ground is supplied to the Engine Control Module (ECM) A/C request input and A/C clutch control signals. The ECM A/C clutch control ground passes through the A/C thermostat and dual pressure switches. If both switches are closed, the ECM will energize A/C cut relay and supply battery voltage to compressor clutch. Battery voltage used to energize A/C clutch is supplied to A/C cut relay through REAR WIPER fuse (10-amp), located in passenger compartment fuse box.
Friday, April 10th, 2009 AT 6:41 PM