General Information
Component Location
General Description
The Engine Coolant Temperature Sensor (ECTS) is located in the engine coolant passage of the cylinder head for detecting the engine coolant temperature. The ECTS uses a thermistor whose resistance changes with the temperature. The electrical resistance of the ECTS decreases as the temperature increases and increases as the temperature decreases. The reference 5V in the ECM is supplied to the ECTS via a resistor in the ECM. That is, the resistor in the ECM and the thermistor in the ECTS are connected in series. When the resistance value of the thermistor in the ECTS changes according to the engine coolant temperature, the output voltage also changes. During cold engine operation the ECM increases the fuel injection duration and controls the ignition timing using the information of engine coolant temperature to avoid engine stalling and improve drivability.
DTC Description
Checking the coolant temperature under detecting condition, if the coolant temperature exceeds the threshold temperature under normal operation loads, ECM sets P0217. MIL (Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
DTC Detecting Condition
Specification
Diagnostic Circuit Diagram
Signal Waveform & Data
Fig.1) Normal data of IATS (89.6 °F) & ECTS (195.8 °F) & EOTS (201.2 °F) after warming up.