Hyundai Elantra MD/UD: Engine Coolant Temperature Sensor (ECTS). Description and Operation
Description
Engine Coolant Temperature Sensor (ECTS) is located in the engine coolant
passage of the cylinder head for detecting the engine coolant temperature. The
ECTS uses a thermistor whose resistance changes with the temperature.
The electrical resistance of the ECTS decreases as the temperature increases,
and increases as the temperature decreases. The reference +5V is supplied to
the ECTS via a resistor in the ECM. That is, the resistor in the ECM and the
thermistor in the ECTS are connected in series. When the resistance value of
the thermistor in the ECTS changes according to the engine coolant temperature,
the output voltage also changes.
During cold engine operation, the ECM increases the fuel injection duration
and controls the ignition timing using the information of engine coolant temperature
to avoid engine stalling and improve drivability.
