Transmission Range (TR) Sensor
WARNING: This page is about a different car, the 2003 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The PCM sends a voltage signal to the TR sensor. The TR sensor incorporates a series of step down resistors which act as a voltage divider. The PCM monitors this voltage which corresponds to the position of the transmission range selector lever (P, R, N, D, 2, 1) to determine desired gear and electronic pressure control (EPC) pressure. The TR sensor is located on the top of the transaxle, and also contains the neutral/start, and backup lamp circuits.