Transmission Fluid Temperature Sensor Assembly

The Automatic Transmission Fluid Temperature (TFT) Sensor Assembly is a thermistor which is mounted in the wiring harness assembly. Low transmission temperature produces high resistance, while high temperature produces low resistance. The VCM/PCM supplies a 5-volt signal to the TFT Sensor Assembly through an internal resistor. Then the VCM/PCM measures the voltage drop in the circuit. Voltage will be high when the transmission is cold and low when the transmission is hot.

The VCM/PCM uses the TFT Sensor Assembly in order to regulate torque converter clutch apply, as well as shift quality.

Code P1712 and P1713 indicate a fault in the TFT Sensor Assembly circuit. After the vehicle has been started, transmission temperature should rise steadily and stabilize between 90 - 115° C, depending on load. Both codes will cause the VCM/PCM to use a default value of 140° C, thus reacting as if the transmission were hot in either case. When Code P1712 or P1713 are set, the VCM/PCM will freeze the shift adapts from being updated, and the MIL will not illuminate. Some driveablity symptoms will be noticed, especially when cold.