S15/T15 2WD Jimmy V6-262 4.3L (1991)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Coolant Temperature Sensor
The engine coolant temperature sensor is a thermistor that is located in the engine coolant flow. When the coolant temperature is low, the sensor
produces a high resistance. When the coolant temperature is high, the sensor produces a low resistance.
The ECM/PCM sends a 5 volt signal to the coolant temperature sensor through a resistor in the computer and measures the voltage. The voltage will be
high or low depending on coolant temperature. By varying the voltage the computer will sense engine coolant temperature.
