Engine Coolant Temperature Sensor (ECTS): Notes
WARNING: This page is about a different car, the 2005 Hyundai Accent and 2004 Hyundai Accent. However, it is still accessible from the selected car via links, so may be relevant.
The engine coolant temperature sensor is located in the engine coolant passage of the cylinder head. It detects the engine coolant temperature and relays signals to the ECM. It employs a thermistor which is sensitive to changes in temperature. The electric resistance of a thermistor decreases in response to temperature increase. The ECM judges engine coolant temperature by the sensor output voltage and provides optimum fuel enrichment when the engine is cold.