DTC P0712: Transmission Fluid Temperature Sensor "A" Circuit Low Input; DTC P0713: Transmission Fluid Temperature Sensor "A" Circuit High Input [09/2014 - 11/2017]: Description

WARNING: This page is about a different car, the 2017 Lexus RC 350, 2017 Lexus RC 300, 2016 Lexus RC 350, 2016 Lexus RC 300, and 2015 Lexus RC 350. 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 terminal THO1 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	1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other The battery voltage is 8 V or more, the engine switch is on (IG) and the starter is off. ATF temperature sensor resistance is less than 79 Ω. 0.5 seconds 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	1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other DTC Detection Condition 1 295 seconds or more have elapsed since the engine was started when the engine coolant temperature or intake air temperature is -29.375°C (-20.875°F) or less. ATF temperature sensor resistance is higher than 156 kΩ. 0.5 seconds 1-trip detection logic DTC Detection Condition 2 10 seconds or more have elapsed since the engine was started when the engine coolant temperature or intake air temperature is more than -29.375°C (-20.875°F). ATF temperature sensor resistance is higher than 156 kΩ. 0.5 seconds 1-trip detection logic	Open in ATF temperature sensor circuit Transmission wire (ATF temperature sensor) ECM	Comes on	DTC stored

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0712

Transmission Fluid Temperature Sensor "A" Circuit Low Input

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other

The battery voltage is 8 V or more, the engine switch is on (IG) and the starter is off.
ATF temperature sensor resistance is less than 79 Ω.
0.5 seconds
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

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other

DTC Detection Condition 1

295 seconds or more have elapsed since the engine was started when the engine coolant temperature or intake air temperature is -29.375°C (-20.875°F) or less.
ATF temperature sensor resistance is higher than 156 kΩ.
0.5 seconds
1-trip detection logic

DTC Detection Condition 2

10 seconds or more have elapsed since the engine was started when the engine coolant temperature or intake air temperature is more than -29.375°C (-20.875°F).
ATF temperature sensor resistance is higher than 156 kΩ.
0.5 seconds
1-trip detection logic

Open in ATF temperature sensor circuit
Transmission wire (ATF temperature sensor)
ECM

Comes on

DTC stored