Transmission Temperature Sensor

WARNING: This page is about a different car, the 2003 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

The Transmission Range (TR) sensor has an integrated thermistor that the PCM uses to monitor the transmission's sump temperature. Since fluid temperature can affect transmission shift quality and convertor lock-up, the PCM requires this information to determine which shift schedule to operate in. The PCM also monitors this temperature data so it can energize the vehicle cooling fan(s) when a transmission "overheat" condition exists. If the thermistor circuit fails, the PCM will revert to calculated oil temperature usage. A failure in the temperature sensor or circuit will result in calculated temperature being substituted for actual temperature. Calculated temperature is a predicted fluid temperature which is calculated from a combination of inputs:

Battery (ambient) temperature.
Engine coolant temperature.
In-gear run time since start-up.