P0118

P0118 ECT SENSOR




Component Description
The engine coolant temperature sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the ECM. The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

Reference Data:

CAUTION: Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECM's transistor. Use a ground other than the ECM terminals, such as the ground.

On Board Diagnosis Logic
Malfunction is detected when an excessively high (P0118) or low (P0117) voltage from the sensor is sent to ECM.

POSSIBLE CAUSE
- Harness or connectors
(The sensor circuit is open or shorted.)

- Engine coolant temperature sensor




FAIL-SAFE MODE
When this malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.

DTC Confirmation Procedure

NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch OFF and wait at least 5 seconds before conducting the next test.

With CONSULT-II
1. Turn ignition switch ON.
2. Select "DATA MONITOR" mode with CONSULT-II.




3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to "Diagnostic Procedure" below.

With GST
Follow the procedure "With CONSULT-II".

EC-ECTS-01:

Wiring Diagram


Diagnostic Procedure

Step 1 - 3:

Step 4 - 5: