Vehicles That Cannot Obtain Speed Pulse Data; Conditions Likely To Cause Noticeable Positioning Errors - Pioneer AVIC-X1 Operation Manual

When driving through a dense forest or tall trees
• If a car phone or cellular phone is used near
the GPS aerial, GPS reception may be lost tem-
porarily.
• Do not cover the GPS aerial with spray paint or
car wax, because this may block the reception
of GPS signals. Snow buildup can also
degrade the signals, so keep the aerial clear.
❒ If, for any reason, GPS signals cannot be
received, learning and error correction are not
possible. If GPS positioning has been operat-
ing for only a short time, your vehicle's actual
position and the current location mark on the
map may diverge considerably. Once GPS
reception is restored, accuracy will be recov-
ered.
Vehicles that Cannot Obtain
Speed Pulse Data
❒ The speed pulse data comes from the speed
sensing circuit. The location of this speed
sensing circuit depends on your vehicle
model. In some cases, it is impossible to
make a connection to it, and in such a case
we recommend that the ND-PG1 speed pulse
generator (sold separately) be used.
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Conditions Likely to Cause
Noticeable Positioning Errors
For various reasons such as the state of the road
you are travelling on and the state of reception of
the GPS signal, the actual position of your vehicle
may differ from the position displayed on the map
screen.
• If you make a slight turn.
• If there is a parallel road.
• If there is another road very nearby, for exam-
ple, an elevated motorway.
• If you take a recently opened road that is not
on the map.