Cadillac 2009 owner manual Global Positioning System GPS, Vehicle Positioning

Global Positioning System (GPS)

The navigation system determines the position of the vehicle by using satellite signals, various vehicle signals, and map data.

At times, other interferences such as the satellite condition, road configuration, the condition of the vehicle and/or other circumstances can interfere with the navigation system’s ability to determine the accurate position of the vehicle.

The GPS shows the current position of the vehicle using signals sent by the GPS Satellites of the United States Department of Defense. When the vehicle is not receiving signals from the satellites, a symbol appears on the map screen. Refer to Symbols on page 4-16.

This system may not be available or interferences may occur if any of the following are true:

•Signals are obstructed by tall buildings, trees, large trucks, or a tunnel.

•Objects are located on the front dash of the vehicle.

•Satellites are being repaired or improved.

•After-market glass tinting has been applied to the vehicle’s windshield.

Notice: Do not apply after-market glass tinting to the vehicle’s windows. Glass tinting interferes with the system’s ability to receive GPS signals and causes the system to malfunction. The window might have to be replaced to correct the problem. This would not be covered by the warranty.

For more information if the GPS is not functioning properly, see If the System Needs Service on page 4-56and Problems with Route Guidance on page 4-55.

Vehicle Positioning

At times, the position of the vehicle on the map may be inaccurate due to one or more of the following reasons:

•Road system has changed.

•Vehicle is driving on slippery road surfaces such as in sand, gravel, and/or snow.

•Vehicle is traveling on winding roads.

•Vehicle is on a long straight road.

•Vehicle is approaching a tall building or a large vehicle.

•Surface streets run parallel to a freeway.

•Vehicle has just been transferred by a vehicle carrier or a ferry.

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