Circuit Description

A thermistor built into the engine coolant temperature sensor changes the resistance value according to the engine coolant temperature.

The structure of the sensor and connection to the ECM is the same as in the intake air temperature circuit malfunction shown on DTC P0110 INTAKE AIR TEMPERATURE CIRCUIT .

If the ECM detects the DTC P0115, it operates the fail-safe function in which the engine coolant temperature is assumed to be 80°C (176°C).

Fig 1: DTC Detecting Condition Chart

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HINT:

After confirming DTC P0115, use the OBD II scan tool or hand-held tester to confirm the engine coolant temperature from the CURRENT DATA.