See also:

Tachometer
The tachometer displays the engine speed in revolutions per minute (rpm). ...

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 ...

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. ...