DTC P0115-11: Engine Coolant Temperature Sensor 1 Circuit Short to Ground [10/2018 - ]: Description

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

The thermistor with a resistance that varies according to the temperature of the engine coolant. When the engine coolant temperature is low, the resistance of the thermistor increases. When the temperature is high, the resistance drops. These variations in resistance are transmitted to the ECM as voltage changes (see Fig. 1 in illustration above).

The engine coolant temperature sensor is powered by a 5 V supply from the THW terminal of the ECM, via resistor R.

Resistor R and the engine coolant temperature sensor are connected in series. When the resistance value of the engine coolant temperature sensor changes, according to changes in the engine coolant temperature, the voltage at terminal THW also varies.

HINT:

When DTC P011511 is stored, the ECM enters fail-safe mode. During fail-safe mode, the engine coolant temperature is estimated to be 80°C (176°F) by the ECM. Fail-safe mode continues until a pass condition is detected.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P011511	Engine Coolant Temperature Sensor 1 Circuit Short to Ground	The engine coolant temperature sensor output voltage is less than 0.142 V for 0.5 seconds or more (1 trip detection logic).	Short in engine coolant temperature sensor circuit Engine coolant temperature sensor ECM	Comes on	DTC stored	SAE Code: P0117

HINT:

When this DTC is output, check the engine coolant temperature in the Data List. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.

Refer to DATA LIST / ACTIVE TEST [10/2018 - 08/2021] Refer to DATA LIST / ACTIVE TEST [08/2021 - ]

DTC No.	Coolant Temperature	Malfunction
P011511	Higher than 135°C (275°F)	Short to ground in THW circuit

If the Data List value is normal, it may be due to a temporary recovery from the malfunction condition. Check for intermittent problems.