Circuit Description

A thermistor is built in the Engine Coolant Temperature (ECT) sensor and changes the resistance value according to the engine coolant temperature.

The structure of the sensor and connection to the ECM is the same the Intake Air Temperature (IAT) sensor.

HINT:

If the ECM detects the DTC "P0115, P0117 or P0118", it operates the fail-safe function in which the ECT is assumed to be 80°C (176°F).

Fig 1: Engine Coolant Temperature Graph

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Fig 2: DTC P0115, P0117 Or P0118 Detection Condition & Trouble Area Table

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HINT:

After confirming DTC P0115, P0117 or P0118, confirm the engine coolant temperature using the menu "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL" on the hand-held tester.