Kia Optima Hybrid: Engine Control System / Engine Coolant Temperature Sensor (ECTS) Description and Operation

Kia Optima Hybrid (TF HEV) 2016-2020 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 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.

Intake Air Temperature Sensor (IATS) Repair procedures

Inspection 1. 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. Temperature ...

Engine Coolant Temperature Sensor (ECTS) Specifications

Specification TemperatureResistance (k?)°C°F-40-4048.14-20-414.13 ~ 16.830325.7920682.31 ~ 2.59401041.15601400.59801760.32 ...

Other information:

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: Power Seat Motor Repair procedures


Inspection Power Seat Motor 1. Disconnect the connectors for each motor. A : Front height motor B : Slide motor C : Rear height motor D : Recline motor E : Lumber support motor 2. With the battery connected directly to the motor terminals, check if the motors run smoothly. 3. Reverse the connections ...

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: Troubleshooting


Warning Lamp Activation Warning Lamp Behavior after Ignition On As soon as the operating voltage is applied to the SRSCM ignition input, the SRSCM activates the warning lamp for a LED lamp check. The lamp shall turn on for 6 seconds during the initialization phase and be turned off afterward. To alert ...

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