Accelerator Pedal Position Sensor: Description and Operation

The Accelerator Pedal Position (APP) Sensor is a Hall Effect, angle of rotation sensor. The Accelerator Pedal Position sensor is located inside the accelerator pedal assembly. A magnet located in the pedal shaft cylinder rotates around a hall effect pick-up. The voltage signal increases as the accelerator pedal depresses. The APP sensor receives a 5 volt reference signal from the ECM and based upon the position of the pedal shift magnet relative to the windows on the Hall effect sensor, a portion of the 5 volts is returned to the ECM indicating pedal position.