GM Service Manual Online
For 1990-2009 cars only

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

The Global Positioning System (GPS) locates the current position of your vehicle using signals sent by the United States Department of Defense GPS satellites. While your vehicle is receiving signals from these satellites, GPS will not appear on the map screen.

However, at times, other interferences such as the satellite condition, road configuration, the condition of the vehicle and/or other circumstances can interfere with the system's ability to determine the accurate position of the vehicle. This is when GPS will appear on the map screen.

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

    • Signals are obstructed by tall buildings, large trucks or a tunnel.
    • Metallic objects are located on the dashboard.
    • Satellites are being repaired or improved.
    • Aftermarket glass tinting has been applied to the vehicle's windshield.

Do not apply aftermarket glass tinting to the vehicle's windshield or place metallic objects on the vehicle's dashboard. Glass tinting and metallic objects will interfere with the system's ability to receive GPS signals and may cause the system to malfunction.

If you are experiencing a problem, see Vehicle Positioning and Problems with Route Guidance for more information.