TTY Users
OnStar has the ability to communicate to the deaf, hard–of–hearing, or speech–impaired customers while in the vehicle.
The available dealer–installed TTY system can provide in-vehicle access to all of the OnStar services, except Virtual Advisor and OnStar Turn–by–Turn Navigation.
See also:
Power Lumbar
To adjust the lumbar support,
if equipped:
- Press and hold the top of the
control (B) to increase support to
the top of the seatback and
decrease support to the bottom
of the seatback.
- ...
Traction – AA, A, B, C
The traction grades, from
highest to lowest, are AA, A,
B, and C. Those grades
represent the tire's ability to
stop on wet pavement as
measured under controlled
conditions on specified
g ...
Map Database Information
Use the Map Database Information/ Remove Map Data screen button to view the coverage
areas of the map database or to replace the map database.
1. Press the Map Database Information/Remove Map Dat ...






