Conditions for Setting the DTC

WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.

The control module detects a pressure change that is less than a calibrated amount.
Several tests must be completed to report a Fail with up to 17 hours between tests.