The Engine Coolant Temperature(ECT) Sensor measures the temperature of engine coolant. The Engine Coolant Temperature (ECT) Sensor is located near the thermostat housing of the cylinder head. ECT Sensor is a thermistor (A Variable Resistor that Changes Along with ECT) in series with a fixed resistor in the Engine Control Module (ECM). The ECM applies 5 volts to the ECT sensor. The ECM monitors the voltage across the ECT sensor and converts it into a temperature reading. When the engine is cold the ECT sensor resistance is high, and when the engine is warm the ECT sensor resistance is low. Therefore, when the engine is cold the ECM will receive a high voltage input, and when the engine is warm the ECM will receive a low voltage input. The signal from ECT sensor is used for Injection control, ignition timing, idle speed and cooling fan control.
If there is no Engine Coolant Temperature Sensor signal change during driving, ECM sets this code(P0116).
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Rationality check | 1. Poor connection 2. ECTS |
Enable Conditions |
•
No vehicle speed sensor error detected
•
Modeled temp. ≥ 45℃ | |
Threshold Value |
•
Measured temp. stuck
•
Modeled temp. - Measured temp. > 15℃ | |
Diagnostic Time |
•
- | |
MIL ON Condition |
•
3 driving cycle |
Temperature [°C (°F)] | Resistance [kΩ] |
-40(-40) | 48.14 |
-20(-4) | 14.13~16.83 |
0(32) | 5.79 |
20(68) | 2.31~2.59 |
40(104) | 1.15 |
60(140) | 0.59 |
80(176) | 0.32 |
