Your Responsibility
Increase the volume of the radio if the OnStar Advisor cannot be heard.
If the light next to the OnStar buttons is red, the system may not be functioning properly. Push 
and request a vehicle diagnostic check. If the light appears clear (no light appears), your OnStar subscription has expired and all services have been deactivated.
Push to confirm that the OnStar equipment is active.
See also:
Time and Date Settings
From the Time and Date Settings screen button, press to display the Time and
Date Settings menu.
Set Time: Press + or − to increase or decrease the Hours and Minutes displayed
on the clock. ...
StabiliTrak® Indicator Light
This light comes on briefly
while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light will then go of ...
Sheet Metal Damage
If the vehicle is damaged and requires sheet metal repair or replacement, make sure the body repair shop applies anti-corrosion material to parts repaired or replaced to restore corrosion protection.
...