GM Service Manual Online
For 1990-2009 cars only

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

    • The road system has changed.
    • The vehicle is traveling on slippery road surfaces such as sand, gravel and/or snow.
    • The vehicle is being driven on winding roads.
    • The vehicle is being driven on a long straight road.
    • The vehicle is approaching a tall building or a large vehicle.
    • The surface streets run parallel to a freeway.
    • The vehicle has just been transferred by a vehicle carrier or a ferry.
    • The current position calibration is set incorrectly.
    • The vehicle is being driven at high speeds.
    • The vehicle is repeating a change of directions by going forward and backward, or turning on a turn table in a parking lot.
    • The vehicle is entering and/or exiting a parking lot, garage or a lot with a roof.
    • The vehicle has a roof carrier installed on it.
    • The vehicle has tire chains on it.
    • The tires have been replaced.
    • The tire pressure is incorrect.
    • The tires are worn.
    • The first time the CD is inserted.
    • The battery is disconnected for several days.
    • The vehicle is driven in heavy traffic where driving is at low speeds and the vehicle is stopped and started repeatedly.

To relocate the vehicle position on the map, see "Adjust Position" under Screen Setup .