C 1500 Truck 2WD V8-6.5L DSL Turbo VIN F (1998)
Transmission Temperature Sensor/Switch: Description and Operation
4L60-E Automatic Transmission
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.
