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:
Entry Lighting
The headlamps, parking lamps, taillamps, and most of the interior lamps turn
on briefly when is pressed on the
Remote Keyless Entry (RKE) transmitter. After about 30 seconds the exterior lamps
...
Radio(s)
Radio with CD (MP3) shown, Radio with Six-Disc CD (MP3) similar
The vehicle has one of these radios as its audio
system. ...
Ultrasonic Parking Assist
If available, Ultrasonic Rear Parking
Assist (URPA) system uses sensors
on the rear bumper to assist with
parking and avoiding objects while
in R (Reverse). It operates at
speeds less than 8 ...