The TR sensor

Fig 1: Identifying TR Sensor, Cover Plate And Actuating Rod

Courtesy of FORD MOTOR CO.

The TR sensor is attached to the transmission housing. A cover plate is attached to the actuation shaft on both sides of the TR sensor. Operation of the selector lever rotates the shaft and therefore also the cover plate.

The TR sensor is a double contactless inductive sensor. It functions essentially in a similar way to a transformer. First, the incoming DC voltage is converted into AC voltage. The cover plates are moved when the selector lever is moved. This causes the magnetic fields to change and the induced AC voltages in the secondary coils therefore also change. These voltage changes are evaluated in the integrated electronics and converted into two digital signals (PWM signals).

The TR sensor is hard-wired to the TCM. On the basis of the two PWM signals, the TCM detects the position of the selector lever.