For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningWindows
WARNING
Never leave a child, a helpless adult, or a pet alone in a vehicle, especially
with the windows closed in warm or hot weather.
They can be overcome by the extreme heat and suffer permanent injuries or even
death from heat stroke.
The vehicle aerodynamics are designed to improve fuel ...
Vehicle Access
Specifications
Door Lock/Indicator Schematics
Door Control Module Schematics
Release Systems Schematics
Fuel Tank Filler Door Lock Actuator Replacement
Preliminary Procedure
Remove the fuel tank filler housing. Refer to Fuel Tank Filler Pipe Housing ...
Exit Lighting
The headlamps, taillamps, parking lamps, back-up lamps, and license plate lamps
come on at night, or in areas with limited lighting, when the key is removed from
the ignition.
The dome lamps also come on when the key is removed from the ignition. The exterior
lights and dome lamps remain on a ...