Diagnostic Aids

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.

There are no driveability issues associated with the APP module unless a DTC is present. The most likely cause of this DTC are faulty connections or the sensor itself. The least likely is a PCM condition.

An intermittent may be caused by the following conditions:

Faulty connections.
Rubbed-through wire insulation.
Broken wire inside the insulation.

A scan tool reads the APP 1 position in volts. The APP 1 position should read approximately 0.45-0.95 volt with the throttle closed and the ignition ON or at idle. The voltage should increase at a steady rate as the throttle is moved toward Wide Open Throttle (WOT). Also, 90 percent pedal travel is acceptable for correct APP operation. Scan the APP 1 sensor while depressing the accelerator pedal with the engine stopped and the ignition ON. The display should vary from approximately 0.74 volt when the throttle was closed to more than 3.7 volts when the throttle is held at WOT position. The following chart will check the voltages on all the APP circuits to see if the voltages are in normal ranges. The PCM compares pre-scaled voltages, which are voltages that the scan tool cannot read. The scan tool reads only output voltages.