Accelerator Pedal Position Sensor
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Suburban, and 2003 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The accelerator pedal assembly contains 2 individual Accelerator Pedal Position (APP) sensors within the assembly. See Fig 1 . The APP sensors 1 and 2 potentiometer-type sensors have a 5-volt reference circuit, low reference circuit and signal circuit. The APP sensors are used to determine pedal angle. The control module provides each APP sensor a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module with signal voltage proportional to pedal movement. Both APP sensor signal voltages are low at rest position and increase as pedal is applied.