P0116

P0116 ECT SENSOR

TYPE A : 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]

TYPE A : DTC Logic

DTC DETECTION LOGIC

NOTE:
If DTC P0116 is displayed with DTC P0117 or P0118, first perform the trouble diagnosis for DTC P0117, P0118. P0117.

DTC CONFIRMATION PROCEDURE
1.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.
TEST CONDITION:
Before performing the following procedure, do not add fuel.
- GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and warm it up to normal operating temperature.
2. Rev engine up to 2,000 rpm for more than 10 minutes.
3. Move the vehicle to a cool place, then stop engine.
4. Check resistance between "fuel level sensor unit and fuel pump (main)" terminals 4 and 5.
5. Soak the vehicle until the resistance between "fuel level sensor unit and fuel pump (main)" terminals 4 and
5 becomes 0.5 kOhm(s) higher than the value measured before soaking.

CAUTION:
Never turn ignition switch ON during soaking.

NOTE:
Soak time changes depending on ambient air temperature. It may take several hours.
6. Start engine and let it idle for 20 minutes.
7. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Go to SEE TYPE A : Diagnosis Procedure.
NO - INSPECTION END

TYPE A : Diagnosis Procedure
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in Circuit Inspection.
Is the inspection result normal?
OK - GO TO 2.
NG - Repair or replace ground connections.
2.CHECK ENGINE COOLANT TEMPERATURE SENSOR
SEE TYPE A : Component Inspection.
Is the inspection result normal?
OK - GO TO 3.
NG - Replace engine coolant temperature sensor. Exploded View.
3.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END

TYPE A : 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. Exploded View.

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

Is the inspection result normal?
YES - INSPECTION END
NO - Replace engine coolant temperature sensor.

TYPE B : Description

[Reference data]

TYPE B : 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. SEE TYPE B : 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 SEE TYPE B : 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.
TEST 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 SEE TYPE B : Diagnosis Procedure.
NO - INSPECTION END

TYPE B : 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. Exploded View

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 SEE TYPE B : Diagnosis Procedure.
2.CHECK INTERMITTENT INCIDENT
Check intermittent incident. Intermittent Incident.
Is the inspection result normal?
YES - INSPECTION END
NO - Proceed to SEE TYPE B : Diagnosis Procedure.

TYPE B : Diagnosis Procedure
1.CHECK ENGINE COOLANT TEMPERATURE (ECT) SENSOR
Check ECT sensor. SEE TYPE B : Component Inspection.
Is the inspection result normal?
OK - GO TO 2.
NG - Replace ECT sensor. Exploded View.
2.CHECK INTERMITTENT INCIDENT
Check intermittent incident. Intermittent Incident.
- INSPECTION END

TYPE B : 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. Removal And Installation.

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

Is the inspection result normal?
YES - INSPECTION END
NO - Replace engine coolant temperature sensor.