P0116
P0116 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]
*: This data is reference value and is measured between ECM terminal 73 (Engine coolant temperature sensor) and 67 (Sensor ground).
CAUTION:
Never 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 ECM terminals, such as the ground.
On Board Diagnosis 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. Refer to [Water Outlet and Water Piping: Removal and Installation] Water Outlet Removal and Installation.
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. Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.
Is the inspection result normal?
YES
INSPECTION END
NO
Proceed to "Diagnosis Procedure".
Diagnosis Procedure
1. CHECK ENGINE COOLANT TEMPERATURE (ECT) SENSOR
Check ECT sensor. Refer to "Component Inspection".
Is the inspection result normal?
YES
GO TO 2.
NO
Replace ECT sensor. Refer to [Water Outlet and Water Piping: Removal and Installation] Water Outlet Removal and Installation.
2. CHECK INTERMITTENT INCIDENT
Check intermittent incident. Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.
INSPECTION END
Component Inspection
Engine Coolant Temperature Sensor
1) Check resistance between engine coolant temperature sensor terminals 1 and 2 as shown in the figure.
2) If NG, replace engine coolant temperature sensor. Refer to [Water Outlet and Water Piping: Removal and Installation] Water Outlet Removal and Installation.