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If you suspect a failure
■ GPS does not perform positioning
・ Immediately after the power is turned on, it may take some time until positioning is initiated.
・ The GPS radio signals cannot be received under elevated railway tracks and in tunnels.
Move to a place where the sky can be seen.
・ Positioning may not be performed accurately in places which are susceptible to multipath such as between dense
trees and near high buildings.
Multipath…A phenomenon where radio waves transmitted from a satellite are reflected and diffracted by obstacles such as buildings
and land features and the same radio waves are received through multiple channels on the receiving side, causing an error
in position information. Places which are easily affected by multipath include places between high buildings and side roads
of elevated highways. When driving in such places, more errors may be observed or positioning may not be performed.
However, since it depends on the position and condition of the car and the acquisition condition of the satellite, it does not
mean that multipath occurs on all cars at the same place in the same way.
・ Be careful to install the GPS antenna in an appropriate place. Positioning may not be performed accurately
depending on the place where it is installed. In addition, failure to place the provided antenna plate properly may
also cause a reduction in sensitivity. Be sure to place the antenna plate properly.
・ Installing the GPS antenna near an electronic device which generates noise may prevent accurate positioning.
●Devices which may affect GPS reception
Car navigation system, cell phone charger and mobile device,
monitor display, car power inverter, radar detector, window sign
of taxi, and other radio devices, etc.
■Pay attention to the material of the windshield
Some cars have a windshield made of a material that blocks radio signals.
If the radio signals from the satellites are shut out, the GPS cannot perform
positioning. Materials such as heat reflective, heat absorbing, and UV-reducing
glass may cause a reduction in sensitivity.
■Install the GPS antenna at a place where the sky can be clearly seen
Install the GPS antenna in a place around the colored area in the photo on the
left where the sky can be clearly seen so that the radio signals from the GPS
satellites can be received well.
Install the GPS antenna as far away as possible from noise
generation sources.
Devices generating noise
They may interfere with the
reception of GPS