Limitations Of The Navigation System - Lexus 2003 LS Owner's Manual

Limitations of the Navigation System

This navigation system calculates the
current vehicle position using satellite
signals, various vehicle signals, map
data, etc. However, the accurate position
may not be shown depending on the sat-
ellite condition, road configuration, ve-
hicle condition or other circumstances.
The Global Positioning System (GPS) devel-
oped and operated by the U.S. Department
of Defense provides an accurate current ve-
hicle position using 3 to 4 satellites. The GPS
system has a certain level of inaccuracy built
in for security reasons. While the navigation
system will compensate for this most of the
time, occasional positioning errors up to 300
feet can and should be expected. Generally,
position errors will be corrected within a few
seconds.
1UE087a
When your vehicle is receiving signals from
the satellites, the "GPS" mark appears at the
top left of the screen.
The GPS signal may be physically ob-
structed, leading to inaccurate vehicle posi-
tion on the map display. Tunnels, tall build-
ings, trucks, or even the placement of
objects on the instrument panel may obstruct
the GPS signals.
The installation of window tinting may also
obstruct the GPS signals. Most window tint-
ing contains some metallic content that will
interfere with the GPS signal reception. We
recommend not to use the window tinting on
vehicles equipped with navigation systems.
The GPS satellites may not send signals due
to repairs or improvements being made to
them.
Even when the navigation system is receiv-
ing good GPS signals, the vehicle position
may not be shown accurately or inappropri-
ate route guidance may occur in some
cases.
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