DTC P0712: Transmission Fluid Temperature Sensor "A" Circuit Low Input; DTC P0713: Transmission Fluid Temperature Sensor "A" Circuit High Input [04/2013 - 08/2015]: Description

WARNING: This page is about a different car, the 2015 Lexus IS 250 and 2014 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.

The ATF (Automatic Transmission Fluid) temperature sensor converts the fluid temperature into a resistance value which is input into the ECM.

The ECM applies a voltage to the temperature sensor through OIL terminal of the ECM.

The sensor resistance changes with the transmission fluid temperature. As the temperature becomes higher, the sensor resistance decreases.

One terminal of the sensor is grounded so that the sensor resistance decreases and the voltage goes down as the temperature becomes higher.

The ECM calculates the fluid temperature based on the voltage signal.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory
P0712	Transmission Fluid Temperature Sensor "A" Circuit Low Input	ATF temperature sensor resistance is less than 79 Ω for 0.5 sec. or more (1-trip detection logic)	Short in ATF temperature sensor circuit Transmission wire (ATF temperature sensor) ECM	Comes on	DTC stored
P0713	Transmission Fluid Temperature Sensor "A" Circuit High Input	ATF temperature sensor resistance is more than 156 kΩ for 0.5 seconds or more. Either of the following conditions is met (1 trip detection logic): Condition (A): 297 seconds or more have elapsed after the engine start when engine coolant temperature or intake air temperature is -29.375°C (-20.875°F) or less. Condition (B): 10 seconds or more have elapsed after the engine start when engine coolant temperature and intake air temperature are more than -29.375°C (- 20.875°F).	Open in ATF temperature sensor circuit Transmission wire (ATF temperature sensor) ECM	Comes on	DTC stored