Dual Differential Potentiometer Sensing for Trailer Control

A controller and method for controlling trailer service braking on a tractor-trailer vehicle are provided. The controller receives a signal from a trailer hand control apparatus, disposed in the cab of the tractor, that is manually activated by a driver. The signal received by the controller includes a differential signal obtained from two sensors having values that change in opposite directions based on movement of the trailer hand control apparatus. Based on the signal, the controller outputs a control signal that is output to a valve controller which controls the application of the trailer service brakes.