Multi-Band Antenna
The antenna located on the roof of the vehicle is used for the OnStar, XM Satellite Radio Service System, and GPS (Global Positioning System), if the vehicle has these features. Keep the antenna clear of obstructions for clear reception.
If the vehicle has a sunroof and it is open, the performance of OnStar, XM, and GPS can be affected.
See also:
Automatic Transmission Shift Lock Control Function Check
WARNING
When you are doing this inspection, the vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before starting this check, be sure there is enough room ...
Tire Pressure
Tires need the correct amount of
air pressure to operate
effectively.
Notice: Neither tire
underinflation nor
overinflation is good.
Underinflated tires, or tires
that do not have enough a ...
Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on
a specified government test
course. For example, a tire
graded 150 ...