Radiator Cooling Fan Speed Sensor: Description and Operation
ENGINE CONTROL COMPONENTSFan Speed Sensor (FSS)
The FSS is a Hall effect sensor integral to the visctronic drive fan (VDF). The PCM monitors the sensor input and controls the VDF speed based upon the engine coolant temperature, the transmission fluid temperature, and the intake air temperature (IAT) requirements. When an increase in fan speed for vehicle cooling is requested, the PCM monitors the FSS signal and outputs the required PWM signal to a fluid port valve within the VDF.