Up to VIN S5219999

Engine cooling fan
With the Ignition Switch in ON or START, the ENG fuse supplies battery voltage to the coil of the engine cooling fan relay. When the engine coolant temperature reaches 207°F (97°C), the Engine Coolant Temperature (ECT) switch closes and grounds the coil, energizing the relay. The engine cooling fan relay contacts close and the COOLING FAN fuse supplies battery voltage to the engine cooling fan motor. The fan motor runs until the coolant temperature drops below 194°F (90°C), the ECT switch opens, the relay is de-energized and the fan motor stops. The engine cooling fan motor is also activated when the Engine Control Module (ECM) senses air conditioning operation. This reduces coolant temperature in compensation for the additional load from the A/C system. In this case, the engine cooling fan relay is grounded through the A/C relay and through the ECM.

Condenser fan
With the ignition switch in ON, battery voltage is supplied to the coil of the A/C relay. Operating parameters permitting, the coil of the relay is grounded through the ECM whenever the A/C switch is ON. (See Compressor Controls). The A/C relay energizes and supplies battery voltage to the coil of the condenser fan relay. The condenser fan relay energizes and supplies battery voltage to the condenser fan motor, activating the motor.