Owner's Manual
Page 204
...map matching Handling large errors Positioning errors are susceptible to a nearby road. If a car phone or cellular phone is impossible for a long time, your position by adjusting it is used by this navigation system are kept to use GPS positioning. This is restored, accuracy will be updated.... When driving among high buildings When driving through a dense forest or tall trees ! In such case, once GPS reception is called map matching.
...map matching Handling large errors Positioning errors are susceptible to a nearby road. If a car phone or cellular phone is impossible for a long time, your position by adjusting it is used by this navigation system are kept to use GPS positioning. This is restored, accuracy will be updated.... When driving among high buildings When driving through a dense forest or tall trees ! In such case, once GPS reception is called map matching.