The travel distance sensor is mostly located in the rear axle or at the gearbox.

It is measuring the rotational speed of the wheels or the transmission.

The measured data is used by the engine management to determine the vehicle speed and bye the cruise control system.

If the travel distance sensor fails the engine management will issue a diagnostic trouble code and illuminate the check engine light.

Also the driver might experience problems with the speedometer and the cruise control system.

The main reasons for a defective automatic transmission speed sensor are broken cables or corrosion of the sensor electronic or the sensor ring.