ECT Sensor For California

P0116 ECT SENSOR

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.













DTC Logic


DTC DETECTION LOGIC







DTC CONFIRMATION PROCEDURE


1. INSPECTION START

Is it necessary to erase permanent DTC?
YES- GO TO 3.
NO- GO TO 2.

2. PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to "Component Function Check".
NOTE:
Use the component function check to check the overall function of the ECT sensor circuit. During this check, a
1st trip DTC might not be confirmed.
Is the inspection result normal?
YES- INSPECTION END
NO- Proceed to "Diagnosis Procedure".

3. PRECONDITIONING

If DTC CONFIRMATION PROCEDURE has been previously conducted, always perform the following procedure before conducting the next test.
1.Turn ignition switch OFF and wait at least 10 seconds.
2.Turn ignition switch ON.
3.Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
- Before performing the following procedure, do not add fuel.
- Before performing the following procedure, check that fuel level is between 1/4 and 4/4.
- Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
- GO TO 4.

4. PERFORM DTC CONFIRMATION PROCEDURE

1.Start engine and let it idle for 60 minutes.
2.Move the vehicle to a cool place.
NOTE:
Cool the vehicle in an environment of ambient air temperature between 10�C (14�F) and 35�C (95�F).
3.Turn ignition switch OFF and soak the vehicle for 12 hours.

CAUTION:
Never turn ignition switch ON during soaking.
NOTE:
The vehicle must be cooled with the food open.
4.Start engine and let it idle for 5 minutes or more.

CAUTION:
Never turn ignition switch OFF during idling.
5.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Proceed to "Diagnosis Procedure".
NO- INSPECTION END


Component Function Check


1. CHECK ENGINE COOLANT TEMPERATURE (ECT) SENSOR

1.Turn ignition switch OFF.
2.Disconnect ECT sensor harness connector.
3.Remove ECT sensor. Service and Repair.





4.Check resistance between ECT sensor terminals by heating with hot water as shown in the figure.





Is the inspection result normal?
YES- GO TO 2.
NO- Proceed to "Diagnosis Procedure".

2. CHECK INTERMITTENT INCIDENT

Check intermittent incident. Intermittent Incident.
Is the inspection result normal?
YES- INSPECTION END
NO- Proceed to "Diagnosis Procedure".


Diagnosis Procedure


1. CHECK GROUND CONNECTION

1.Turn ignition switch OFF.

2.Check ground connection E9. Refer to Ground Inspection in Circuit Inspection.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair or replace ground connection.

2. CHECK ENGINE COOLANT TEMPERATURE SENSOR

Refer to "Component Inspection".
Is the inspection result normal?
YES- GO TO 3.
NO- Replace engine coolant temperature sensor. Service and Repair.

3. CHECK INTERMITTENT INCIDENT

Intermittent Incident.
- INSPECTION END


Component Inspection


1. CHECK ENGINE COOLANT TEMPERATURE SENSOR

1.Turn ignition switch OFF.
2.Disconnect engine coolant temperature sensor harness connector.
3.Remove engine coolant temperature sensor. Service and Repair.





4.Check resistance between engine coolant temperature sensor terminals as follows.





Is the inspection result normal?
YES- INSPECTION END
NO- Replace engine coolant temperature sensor. Refer to
Service and Repair.