174
Reference Inf
o
rmation
System Limitations
GPS System
The signals received from the 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:
•
Metallic window tint on the front or side
windows
•
Cell phones, PDAs, or other electronic
devices docked in a cradle or lying loose
on the dashboard
•
Remote starters or “hidden” vehicle
tracking systems mounted near the
navigation unit
•
Audio electronic devices mounted near
the navigation unit
•
Trees, tall buildings, freeway overpasses,
tunnels, or overhead electrical power
wires
The GPS is operated by the U.S.
Department of Defense. For security
reasons, there are certain inaccuracies built
into the GPS for which the navigation
system must constantly compensate. This
can cause occasional positioning errors of
up to several hundred feet.
Address Calculation
The destination icon shows only the
approximate location of a destination
address. This occurs if the number of
possible addresses is different from the
number of actual addresses on a block. For
example, the address 1425 on a 1400
block with 100 possible addresses
(because it is followed by the 1500 block)
will be shown a quarter of the way down
the block by the system. If there are only
25 actual addresses on the block, the
actual location of address 1425 would be
at the end of the block.
Database
The digitized map database reflects
conditions as they existed at various points
in time before production. Accordingly,
your database may contain inaccurate or
incomplete data or information due to the
passage of time, road construction,
changing conditions, or other causes.
For example, some places/landmarks may
be missing when you search the database
because the name was misspelled, the
place was improperly categorized, or a
place/landmark is not yet in the database.
This is also true for police stations,
hospitals, and other public institutions. Do
not rely on the navigation system if you
need law enforcement or hospital services.
Always check with local information
sources.
FIT_KA-31TK6830.book 174 ページ 2011年7月4日
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