Regarding Errors In Current Position Display - Subaru Impreza 2012 Instruction Manual

• In underground buildings and indoor
parking lots
• Under elevated roads
NOTE
• Because the GPS satellite is in orbit around the earth, the reception status for
the electromagnetic waves changes depending on their position at that point
in time, even if your vehicle is in the same place. Also, electromagnetic-waves
from satellites near the horizon can be easily influenced by surrounding
obstacles.
• At times, satellites under the control of the US Department of Defence will
intentionally drop positioning accuracy.
• In places with a lot of overgrown
trees and so on
• Roads at the base of cliffs and caves

Regarding Errors in Current Position Display

To pinpoint the current position, the unit uses information from GPS
satellite electromagnetic waves. If any of these contain errors, the
current position may not match the actual position.
Further Information
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