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:
Removing the Fence
Unlock by turning both latches (A) to align with the arrow on the
adapter (B). Lift and remove the fence. ...
Tips and Troubleshooting Chart
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Navigation
OnStar navigation requires the Directions and Connections service plan.
Push to receive directions or have them sent to the vehicle navigation
screen. Destinations can also be forwarded to the veh ...