For 1990-2009 cars

The electric cooling fan is used to cool engine coolant flowing through the radiator. The fan is also used to cool the refrigerant (R134a) flowing through the A/C condenser.

The Powertrain Control Module (PCM) controls the operation of the cooling fan. This is accomplished by providing a ground path, for the cooling fan relay coil, within the PCM. The relay contacts will close and complete the circuit between the fuse and the fan motor.

Power for the fan motor comes from a fuse to the cooling fan relay. The relay is energized when current flows from the CLG FAN fuse through the relay coil to ground through the PCM. The Output Driver Module outputs are monitored by the PCM.