Hyundai Veloster: 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 that changes resistance 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.

Inspection
1.
Turn the ignition switch OFF.
2.
Disconnect the IATS connector.
3.
Measure resistance between th ...
Specification
Temperature
Resistance (kΩ)
°C
°F
-40
-40
48.14
-20
-4
...
See also:
Engine
...
Schematic Diagrams
MDPS Circuit Diagram
Harness Connector
Type
Pin NO
Description
Battery
1
Battery +
2
B ...
Room lamp
• ON (1): In the ON position, the light stays on at all times.
• DOOR (2) : In the DOOR position, the light comes on when any door is opened
regardless of the ignition switch position. When d ...