DTC P0221: Accelerator Position Sensor 2 Circuit Performance: Description
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, 2002 Chevrolet RV Cutaway, and 2002 Chevrolet Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
The Accelerator Pedal Position (APP) module provides a voltage signal that changes relative to the accelerator position. There are 3 differently scaled sensors located within the APP module.