Hyundai Ioniq: Engine Control System / Engine Coolant Temperature Sensor (ECTS). Description and operation

Hyundai Ioniq (AE) 2017-2025 Service Manual / Engine Control/Fuel System / Engine Control System / 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.

Intake Air Temperature Sensor (IATS). Repair procedures

Inspection1.Turn the ignition switch OFF.2.Disconnect the IATS connector.3.Measure resistance between the IATS terminals 3 and 4.4.Check that the resistance is within the specification...

Engine Coolant Temperature Sensor (ECTS). Specifications

Specification Temperature Resistance (kΩ) °C °F -40-4048...

Other information:

Hyundai Ioniq (AE) 2017-2025 Service Manual: Description and operation

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Hyundai Ioniq (AE) 2017-2025 Service Manual: Troubleshooting

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