DTC P0115-15: Engine Coolant Temperature Sensor 1 Circuit Short to Battery or Open [03/2023 - ]: Procedure

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READ VALUE USING GTS (CHECK FOR OPEN IN WIRE HARNESS)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Engine Coolant Temperature Sensor	*2	ECM
*a	Front view of wire harness connector (to Engine Coolant Temperature Sensor)	-	-

Disconnect the engine coolant temperature sensor connector.
Connect terminals 1 (E2) and 2 (THW) of the engine coolant temperature sensor connector on the wire harness side.

According to the display on the GTS, read the Data List.

Powertrain > Engine > Data List

Tester Display
Coolant Temperature

GTS Display	Specified Condition
Coolant Temperature	Higher than 135°C (275°F)

HINT:

Perform "Inspection After Repair" after replacing the engine coolant temperature sensor.

Refer to INITIALIZATION [11/2021 - ]

Result

Proceed to
OK
NG

Result:

REPLACE ENGINE COOLANT TEMPERATURE SENSOR. Refer to REMOVAL [11/2021 - ]

Result:

See step 2

CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)

Disconnect the engine coolant temperature sensor connector.
Disconnect the ECM connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
B32-2 (THW) - B92-125 (THW)	Always	Below 1 Ω
B32-1 (E2) - B92-124 (ETHW)	Always	Below 1 Ω
B32-2 (THW) or B92-125 (THW) - Other terminals	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

REPLACE ECM. Refer to REMOVAL [11/2021 - ]

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR