Circuit Description

A thermistor is built in the engine coolant temperature 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 as those of the intake air temperature sensor.

HINT:

If the ECM detects the DTC P0115, P0117 or P0118, it operates the fail-safe function in which the engine coolant temperature is fixed at 80 °C (176°F).

Fig 1: DTC Detection Condition & Trouble Area Chart

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HINT:

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