DTC P0116 Engine Coolant Temperature Circuit Range / Performance Problem: Description

Fig 1: Engine Coolant Temperature Circuit Range Resistance Graph

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A thermistor is built into the Engine Coolant Temperature (ECT) 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 the Intake Air Temperature (IAT) sensor.

HINT:

If the ECM detects the DTC P0115, P0117 or P0118, it operates the fail-safe function in which the ECT is assumed to be 80°C (176°F).

DIAGNOSTIC TROUBLE CODE CHART

DTC No.	DTC Detection Condition	Trouble Area
P0116	If ECT is 35 to 60°C (95 to 140°F) when engine is started, and if conditions (a) and (b) are met: Vehicle has accelerated and decelerated ECT remains within 3°C (5.4°F) of the initial ECT (2 trip detection logic)	Cooling system ECT sensor
P0116	If ECT is more than 60°C (140°F) when engine is started and the vehicle has accelerated and decelerated If ECT sensor records an ECT variation below 1°C (1.8°F) successively 6 times (6 trip detection logic)	Cooling system ECT sensor