Diagnostic Aids
WARNING: This page is about a different car, the 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
If an APP low or high voltage circuit fault DTC is set, diagnose that DTC first. An intermittent circuit fault may also set this DTC.
To locate an intermittent problem, use scan tool to monitor APP sensor 1 and APP sensor 2 with ignition on, engine off. Press accelerator pedal very slowly from the rest to full position, while monitoring each sensor voltage range. Watch for a sharp change in each of the voltage ranges, which would indicate a problem.
Ensure each APP sensor harness connector terminal is not spread and the connector is free of corrosion or foreign material.
APP sensor 2 should always be one half the voltage value of APP sensor 1 during the entire pedal travel range.
Replace the accelerator pedal assembly if a problem was found.