DTC P0116 Engine Coolant Temperature Circuit Range / Performance Problem

DESCRIPTION

A thermistor is built into the Engine Coolant Temperature (ECT) sensor and it changes its resistance value according to the engine coolant temperature.

The structure of the sensor and connection to the ECM is the same as the intake air temperature sensor.

P0116
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
City driving for 10 minutes or more	If the engine coolant temperature is between -40°C (-40°F) and 60°C (140°F) at engine start, and conditions (a) and (b) are met (2 trip detection logic): (a) Vehicle is driven at varying speeds (accelerating and decelerating) for 10 seconds. (b) Engine coolant temperature remains within 3°C (5.4°F) of the engine starting temperature.	Engine coolant temperature sensor
City driving for 10 minutes or more	If the engine coolant temperature is more than 60°C (140°F) at engine start, and conditions (a) and (b) are met (6 trip detection logic): (a) Vehicle is driven at varying speeds (accelerating and decelerating) for 10 seconds. (b) Engine coolant temperature remains within 1°C (1.8°F) of the engine starting temperature.	Engine coolant temperature sensor

Related Data List
DTC No.	Data List
P0116	Coolant Temp

HINT:

If DTC P0116 is stored, the following symptoms may appear:

Misfire

Combustion noise

Black smoke

White smoke

Lack of power

MONITOR DESCRIPTION

The engine coolant temperature sensor is used to monitor the engine coolant temperature. The engine coolant temperature sensor has a thermistor that varies its resistance depending on the temperature of the engine coolant. When the coolant temperature is low, the resistance of the thermistor increases. When the temperature is high, the resistance drops. The variations in resistance are reflected in the voltage output from the sensor. The ECM monitors the sensor voltage and uses this value to calculate the engine coolant temperature. When the sensor voltage output varies slightly, the ECM interprets this as a fault in the engine coolant temperature sensor and sets a DTC.

Examples:

Upon starting the engine, the engine coolant temperature is between -40°C (-40°F) and 60°C (140°F). If after driving for a few minutes, the engine coolant temperature still remains within 3°C (5.4°F) of the starting temperature, a DTC is stored (2 trip detection logic).

Upon starting the engine, the engine coolant temperature is more than 60°C (140°F). If after driving for a few minutes, the engine coolant temperature still remains within 1°C (1.8°F) of the starting temperature, a DTC is stored (6 trip detection logic).

INSPECTION PROCEDURE

HINT:

If DTCs P0115, P0117 and P0118 are stored simultaneously, the engine coolant temperature sensor circuit may have an open or short. Perform troubleshooting for these DTCs first.

Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

1.CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0116)

Connect the intelligent tester to the DLC3.

Turn the ignition switch to ON and turn the tester on.

Enter the following menus: Powertrain / Engine / DTC.

Read the DTCs.

Result
Result	Proceed to
P0116 is output	A
P0116 and other DTCs are output	B

B

GO TO DTC CHART ()

A

2.REPLACE ENGINE COOLANT TEMPERATURE SENSOR

Replace the engine coolant temperature sensor ().

NEXT

3.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

Connect the intelligent tester to the DLC3.

Clear the DTCs ().

Turn the ignition switch off.

After starting the engine, perform city driving for 10 minutes or more.

Confirm that the DTC is not output again.

HINT:

Perform the following procedure using the tester to determine whether or not the DTC judgment has been carried out.

Enter the following menus: Powertrain / Engine / Utility / All Readiness.

Input DTC P0116.

Check that STATUS is NORMAL. If STATUS is INCOMPLETE or UNKNOWN, increase city driving time by 10 minutes and check.

1VD-FTV ENGINE CONTROL

Land Cruiser URJ200 URJ202 GRJ200 VDJ200

ECD SYSTEM w/o DPF