How are speed limits on the nav determined?
 

When my wife and I each bought our 2018 F-Pace and XE respectively, the sales person told us that the cameras near the rear view mirror take photos of speed limit signs, which are then used on the Navigation display.
Can anyone speak to the voracity of that claim?

That’s an option (“Traffic Sign Recognition and Adaptive Speed Limiter”) which I don’t have. In my case, the speed limit that appears on the nav screen comes from the GPS maps.

On my XE and Volvo, it certainly does read speed limit signs as I can see the speed limit change (on the HUD) as soon as I pass the sign.

Thanks DJS, that explains why I'm seeing a disparity between the nav and the speed limit road signs.
Now how to deal with the sales person who fed us a line of $#!π

The NAV also knows about the speed limit. My Aston gets it from Garmin.