Transmission Temperature Sensor/Switch: Description and Operation

The Transmission Fluid Temperature (TFT) sensor is located on the solenoid valve body. It is a temperature-sensitive device called a thermistor. The resistance value of the TFT sensor will vary with temperature. The Powertrain Control Module (PCM) monitors the voltage across the TFT sensor to determine the temperature of the transmission fluid. The PCM uses this signal to determine shift scheduling and to control line pressure for cold and hot temperature operation. The PCM also inhibits Torque Converter Clutch (TCC) operation at low transmission temperature and adjusts Electronic Pressure Control (EPC) pressures for temperature.