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:
How to Inspect the Engine AirCleaner/Filter
To inspect the air cleaner/filter remove the filter
from the vehicle and lightly shake the filter to
release loose dust and dirt. If the filter remains
caked with dirt, a new filter is required.
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Dual Tone Multi-Frequency (DTMF)
Tones
The in-vehicle Bluetooth system can send numbers and
numbers stored as name tags during a call. This is
used when calling a menu driven phone system.
Account numbers can be programmed into the
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Unlock Feedback
Press the customization button until UNLOCK
FEEDBACK: LAMPS appears in the display. To
select your preference for the feedback you will
receive when unlocking the vehicle with the Remote
Keyless E ...