DTC P0115-15: Engine Coolant Temperature Sensor 1 Circuit Short to Battery or Open [10/2022 - ]: Description

WARNING: This page is about a different car, the 2025 Lexus RX 350, 2024 Lexus RX 350, and 2023 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

Refer to DTC P0115-11.

Refer to DESCRIPTION

HINT:

When DTC P0115-15 is stored, the ECM enters fail-safe mode. During fail-safe mode, the engine coolant temperature is estimated to be 80°C (176°F) by the ECM. Fail-safe mode continues until a pass condition is detected.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	DTC Output from	Priority	Note
P0115-15	Engine Coolant Temperature Sensor 1 Circuit Short to Battery or Open	The engine coolant temperature sensor output voltage is higher than 4.91 V for 0.5 seconds or more (1 trip detection logic).	Open or short in engine coolant temperature sensor (for outlet side) circuit Engine coolant temperature sensor (for outlet side) ECM	Comes on	Engine	A	SAE Code: P0118 DTC for Mexico Models: Applies

HINT:

When this DTC is output, check the engine coolant temperature in the Data List. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.

DTC No.	Coolant Temperature	Malfunction
P0115-15	-40°C (-40°F)	Short to +B in THW circuit Open in THW circuit Open in ETHW circuit

If the Data List values is normal it may be due to a temporary recovery from the malfunction condition. Check for intermittent problems.

Refer to CHECK FOR INTERMITTENT PROBLEMS [10/2022 - ]