Temperature Gauge: Description and Operation

Engine Coolant Temperature Gauge Circuit Operation
The Engine Coolant Temperature Gauge Sensor (X114) has approximately 136 ohms resistance when the coolant temperature is low. As coolant temperature increases, the resistance of the sensor decreases. This varying resistance causes the current through the sensor to change and the gauge to register the temperature. When the coolant is hot, the resistance of the sensor is approximately 17 ohms.