K 3500 Truck 4WD V8-6.6L DSL Turbo VIN 1 (2001)
Accelerator Pedal Position Sensor: Description and Operation
ACCELERATOR PEDAL POSITION (APP) SENSOR
The Accelerator Pedal Position (APP) sensor is mounted on the accelerator pedal control assembly. The sensor is made up of 3 individual sensors within
one housing. Three separate signal, low reference, and 5-volt reference circuits are used in order to interface the accelerator pedal sensor assembly with
the ECM. Each sensor has a unique functionality to determine pedal position. The ECM uses the APP sensor to determine the amount of acceleration or
deceleration desired by the person driving the vehicle. The APP sensor 1 voltage should increase as the accelerator pedal is depressed, from below 1.0
volt at 0 pedal travel to above 2 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above 4 volts at 0 pedal travel to below
3.0 volts at 100 percent pedal travel. APP sensor 3 voltage should decrease from above 3.8 volts at 0 percent pedal travel to below 3.3 volts at 100
percent pedal travel.