See also:

Auxiliary Roof-Mounted Lamp
If the vehicle has this feature, this button includes wiring provisions for a dealer or a qualified service center to install an auxiliary roof lamp. This button is located on the overhead console. ...

Engine Identification
The eighth character in the VIN is the engine code. This code identifies the vehicle's engine, specifications, and replacement parts. See “Engine Specifications” under Capacities and Speci ...

Add-on Electrical Equipment
The OnStar system is integrated into the electrical architecture of the vehicle. Do not add any electrical equipment. See Add-On Electrical Equipment on page 9‑112. Added electrical equipment ma ...