Theory Of Operation

Radiator Coolant Temperature Sensor performance compares the outputs of three temperature sensors during vehicle operation; battery pack coolant inlet, battery pack coolant outlet and radiator coolant temperature sensors. If the battery pack coolant temperatures are changing and the radiator coolant temperature is not, the radiator coolant temperature sensor is determined to be not performing. The Radiator Coolant Temperature Sensor is a variable resistor that functions as a normal two wire 5 volt sensor. The Battery Pack Control Module (BPCM) supplies a 5 volt reference and a ground to the sensors low reference signal circuit.