GPS

The signals received from GPS satellites are extremely weak (less than a millionth of the strength of a local FM station) and require an unobstructed view of the sky. The GPS antenna is located in the dashboard. The signal reception can easily be interrupted or interfered with by the following:

• Audio electronic devices mounted near the navigation unit
• Trees, tall buildings, highway overpasses, tunnels, or overhead electrical power wires

GPS is operated by the U.S. Department of Defense. For security reasons, there are certain inaccuracies built into GPS for which the navigation system must constantly compensate. This can cause occasional positioning errors of up to several hundred feet (meters).