Circuit Description
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The transmission fluid temperature (TFT) sensor is part of the pressure switch manifold (PSM) assembly, and is located in the transmission oil pan. The TFT sensor is a thermistor, which changes value based on the temperature of the transmission fluid. The transmission control module (TCM) supplies a 5-volt reference voltage signal to the TFT sensor and measures the voltage drop in the circuit. When the transmission is cold, the sensor resistance is high and the TCM detects high signal voltage. As the fluid temperature warms to a normal operating temperature, the resistance becomes less and the signal voltage decreases. The TCM uses this information to control shift quality and torque converter clutch (TCC) apply.
DTC P0712 is a type B DTC.