WARNING: This page is about a different car, the 2003 Pontiac Montana, 2003 Oldsmobile Silhouette, and 2003 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers on the diagnostic table.
1. The presence of damage to any components of the system.
Fig 1: Automatic Level Control (without inflator) - Diagnostic Chart