DTC P012F-62: Engine Coolant Temperature/Engine Oil Temperature Signal Compare Failure [11/2021 - ]: Description

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The engine is equipped with an engine coolant temperature sensor and an engine oil temperature sensor. The engine coolant temperature sensor and engine oil temperature sensor each have a built-in thermistor. As the temperature decreases, the thermistor resistance increases and as the temperature increases, the thermistor resistance decreases. The voltages at the respective terminals of the ECM change in accordance with the changes in the resistance of the thermistors. The ECM performs control based on these voltages.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Note
P012F-62	Engine Coolant Temperature/Engine Oil Temperature Signal Compare Failure	Either of the following conditions are met (2 trip detection logic): All of the following conditions are met The battery voltage is higher than 8 V. 5 hours or more have elapsed since the engine stopped on the previous trip. The engine oil temperature is -10°C (14°F) or higher. The engine coolant temperature is -10°C (14°F) or higher. The difference between the readings of the engine coolant temperature and engine oil temperature is higher than 20 °C (36 °F). The correlation between the engine coolant temperature sensor and engine oil temperature sensor cannot be validated.	Engine coolant temperature sensor (for outlet side) Engine oil temperature sensor ECM	Comes on	SAE Code: P012F