Transmission Fluid Temperature (TFT) Sensor

WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, and 2003 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.

Transmission Fluid Temperature (TFT) Sensor is located on the solenoid body assembly in the transmission sump.
It is a temperature-sensitive device called a thermistor. The resistance value of the TFT sensor will vary with temperature change.
The powertrain control module (PCM) monitors voltage across the TFT sensor to determine the temperature of the transmission fluid. The PCM uses this signal to determine whether a cold start shift schedule is necessary.
The cold start shift schedule lowers shift speeds to allow for the reduced performance of cold engine operation.
The PCM also uses the TFT sensor input to adjust electronic pressure control (EPC) pressure for temperature effects and to inhibit torque converter clutch (TCC) operation during the warm-up period.