Hombre S Regular Cab 4WD V6-4.3L (1999)
Transmission Temperature Sensor/Switch: Description and Operation
Automatic Transmission Fluid Temperature Sensor
The automatic transmission fluid temperature (TFT) sensor is part of the automatic transmission fluid pressure (TFP) manual valve position switch
assembly. This sensor helps control torque converter clutch apply and shift quality.
The TFT sensor is a resistor, or thermistor, which changes value based on temperature. At low temperatures the resistance is high, and at high
temperatures the resistance is low.
The PCM sends a 5 volt signal to the TFT sensor and the PCM measures the voltage drop in the circuit. You will measure a high voltage when the
transmission is cold and a low voltage when the transmission is hot. Refer to the Temperature vs Resistance table.
If the TFT sensor circuit has a fault, DTC P0712 or P0713 is set. A DTC P0712 indicates a short circuit condition, while a DTC P0713 indicates an
open circuit condition. DTC P0218 is set if the transmission is operating at a high temperature for a period of time.
