Monitor Description
WARNING: This page is about a different car, the 2024 Lexus TX 500h. However, it is still accessible from the selected car via links, so may be relevant.
After the engine has stopped for 5 hours or more, the ECM monitors the voltage of the engine coolant temperature sensor (for outlet side) and engine oil temperature sensor. If the difference between the readings of the engine coolant temperature and engine oil temperature is higher than 20°C (36°F) or the correlation between the engine coolant temperature sensor and engine oil temperature sensor cannot be validated, the ECM determines that there is a malfunction in the engine coolant temperature sensor circuit or engine oil temperature sensor circuit, and stores a DTC and illuminates the MIL.