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. 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".

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.