GMC Sierra
Sierra is a 4-door, up to 6-passenger full size pickup.
See also:
Adjusting the Brightness and Contrast of the Screen
To adjust the brightness and contrast of the screen, press the MENU button while the rear vision camera image is on the display.
Any adjustments made will only affect the rear vision camera screen.
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Onstar.com
The website provides access to account information, manages the OnStar subscription, and allows viewing of videos of each service.
Get subscription plan pricing and sign up for OnStar Vehicle Diagnos ...
Exterior Mirrors
Base Model
To adjust the mirrors:
1. Press or
to select a mirror.
2. Press the control pad to adjust the mirror.
3. Return the switch to the center to deselect the mirror.
Uplevel Model
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