Circuit Description

The oil temperature sensor is a thermistor sensor that is installed in the transmission case and converts temperature changes into continuous electric signals, then outputs them to the Transmission Control Module (TCM). When the ATF temperature is low, the resistance of the sensor (thermistor) goes up, so that the voltage of the TCM signal becomes high.

As the ATF is gradually warmed, the resistance of the sensor goes down and the voltage becomes low. At the normal operating ATF temperature (80°C/176°F) of the transmission, the voltage of the TCM is about 3.7V.