I have a 6250. Every time I enter a tunnel he loses his GPS which is normal but why does the guidance stop, or switch that I am above the tunnel on the road, and until I get out of the tunnel nothing happens? I don't understand why the guidance can't work in the tunnel, why the software isn't set to keep working until it gets a signal. I often have tunnels on the route that have several turns in them, so it becomes impossible to hit right when the signal in the tunnel is lost and the device does not show what to do. It should be set to continue moving along the road until it receives a signal, or to have a sign for the next turn on the display so I can know where to turn.