Cutlass Ciera V6-3300 3.3L MFI VIN N (1993)
Radiator Cooling Fan Motor: Description and Operation
CIRCUIT OPERATION
The Coolant Fan is controlled by the Coolant Fan Relay. The Coolant Fan Relay is electrically operated by the ECM. The ECM receives input
signals from the ECT Sensor, the Vehicle Speed Sensor, and the A/C Mode Selector. The ECM activates the Coolant Fan Relay when:
1. Engine coolant temperature (which is sensed by the ECT Sensor) is above 1OO°C (212°F).
2. The A/C is turned ON and vehicle speed is below 64 Km/h (40 MPH).
3. The ECT Sensor fails.
Any of these input signals causes the ECM to ground circuit 535. With circuit 535 grounded, the Coolant Fan Relay is energized and its contacts
close, turning the Coolant Fan on.