Accuracy Of The Vehicle's Position - Kenwood KNA-DV2100 Instruction Manual

Accuracy of the Vehicle's Position

Area in which GPS signals cannot be received
* Because the radiowave signals from the GPS satellites travel primarily by line of sight, the
navigation system might not be able to receive the signals in the areas described below.
(If the GPS mark does not appear on the map screen, it means that the GPS radiowave
signals are not being properly received.)
(1) Inside a tunnel
(2) Inside a building
(3) Under a three-dimensional road such as a high-speed road
(4) On boulevards lined with trees
(5) Between buildings
(6) Under a cliff or in a cave
• If the GPS antenna or its surroundings are blocked by an obstacle (including cargo), it might
not be possible for the system to receive the GPS radiowave signals.
• If multiple paths are created due to the reflection from the buildings, a large measurement
error could occur, causing the vehicle's mark to deviate from its actual position.
* The vehicle's position mark could deviate from its actual position when the vehicle is being
driven under the conditions listed below or due to conditions of the GPS satellites.
If the vehicle travels on a road whose actual shape differs from that in the map data, the
vehicle's mark could deviate from the actual position. The correct position will eventually
appear on the screen through the correction function. If the screen does not show the
correct position for a long time, correct the current position or make an automatic
correction.
(1) The vehicle's mark could appear on a parallel road.
(2) When the road splits into a narrow Y, the vehicle's mark could appear on the other
fork of the Y.
(3) When the vehicle makes a right or left turn, the vehicle's mark could appear on one
street ahead or behind.
(4) If the vehicle is transported by a means other than the vehicle's own power, such as
on a ferry boat, the vehicle's mark will remain in the position it was before the
transport until the system can calculate the position through the GPS.
(5) When the vehicle is driven on a steep incline, the vehicle's mark could deviate from
its actual position.
(6) If there are continuous gradual curves in the same direction, the vehicle's mark could
deviate from its actual position.
(7) If the vehicle is driven in a zigzag pattern, such as through frequent lane changes, the
vehicle's mark could deviate from its actual position.
(8) If the vehicle is placed on a turntable , such as in a parking area, and turned with the
ignition OFF, the orientation of the vehicle's mark could deviate from its actual
orientation. The vehicle's mark could also deviate even after the vehicle has exited
the parking area.
(9) The vehicle's mark could deviate from its actual position if the vehicle is driven on a
snow-covered road or on a mountainous road with tire chains or snow tires.
* After driving the vehicle under those conditions, perform the same operation given
in the section on "After changing tires".
(10) The vehicle's mark could deviate from its actual position after the tires have been
replaced.
* After replacing the tires, refer to the section on "After changing tires".
Deviation of the vehicle's position mark
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