Possible Causes
Low coolant level
Faulty Engine Coolant Temperature (ECT) Sensor
Stuck or leaking thermostat
Engine Coolant Temperature Sensor harness is open or shorted
Engine Coolant Temperature Sensor circuit poor electrical connection
الأسباب المحتملة
Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
الأعراض المحتملة
Description
This Diagnostic Trouble Code (DTC) is stored in the engine control module when the output from the Engine Coolant Temperature (ECT) Sensor is not as expected or missing. The Engine Control Module (ECM) uses information from the Intake Air Temperature Sensor and Engine Oil Temperature Sensor to carry out a plausibility check on the signal. Engine Coolant Temperature Sensors are normally a negative temperature coefficient thermistor. The signal voltage drops as the engine coolant temperature increases. The signal from the sensor is used to adjust the ignition system rate of advance and fuel injection system duration for various operating conditions. A faulty Engine Coolant Temperature Sensor may result in an engine over fuelling or not entering closed-loop control. The rate of ignition advance is reduced when the engine is hot to reduce the possibility of engine knock occurring.
