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:
When to Check Lubricant
It is not necessary to regularly check rear axle fluid unless there is a leak
suspected or an unusual noise is heard. A fluid loss could indicate a problem. Have
it inspected and repaired.
All ax ...
Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will
check the engine, transmission, antilock brakes, and major vehicle systems.
It also checks the tire pressures, if the v ...
Replacement Bulbs
For replacement bulbs not listed here, contact your dealer. ...