Monitor Description
WARNING: This page is about a different car, the 2006 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.
This DTC indicates that there is a problem with output from the automatic transmission fluid (ATF) temperature sensor (TFT sensor) and that the sensor itself is defective. The ATF temperature sensor converts the ATF temperature to an electrical resistance value. Based on the resistance, the ECM determines the ATF temperature and detects an opens or shorts in the ATF temperature circuit or a fault of the ATF temperature sensor.
After running the vehicle for a certain period, the ATF temperature should increase. If the ATF temperature is below 20°C (68°F) after running the vehicle for a certain period, the ECM interprets this as a fault, and turns on the MIL.