Circuit Description

A thermistor is built into the engine coolant temperature sensor, of which the resistance value varies according to the engine coolant temperature.

The structure of the sensor and its connection to the ECM are the same as those of the intake air temperature sensor.

HINT:

If DTC P0115 is set, the ECM enters fail-safe mode. During fail-safe mode, the engine coolant temperature is assumed to be 80°C (176°F) by the ECM.

Fig 1: DTC Chart

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HINT:

When DTC P0115 is set, check the engine coolant temperature by selecting the following menu items on the hand-held tester or the OBD II scan tool: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.