WARNING: This page is about a different car, the 2002 Pontiac Montana, 2002 Oldsmobile Silhouette, and 2002 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Interior Backlighting Does Not Dim (1 Of 2)
Courtesy of GENERAL MOTORS CORP.
Fig 2: Interior Backlighting Does Not Dim (2 Of 2)