Secondary Cooling System Engine Coolant Temperature 2 (ECT2) Sensor
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The secondary cooling system ECT2 sensor is a thermistor device in which resistance changes with temperature. The electrical resistance of a thermistor decreases as the temperature increases, and resistance increases as the temperature decreases. The varying resistance affects the voltage drop across the sensor terminals and provides electrical signals to the PCM corresponding to temperature.
The secondary cooling system ECT2 sensor is located in the coolant hose on the right side of the core support. The secondary cooling system ECT2 sensor measures the temperature of the secondary cooling system and provides a feedback signal to the PCM.