Car: 10G 1.5 Civic Prestige
Join Date: 10th October 2015
Location: Bexhill, Sussex
Thanked 221 Times in 213 Posts
That's what I would try first using the same USB stick and the stuff that's already on it.
Do you have the satnav menus, or is it completely borked. If not and you happen to have another stick, try the update from scratch (put it in your PC and do the map update thing) on the alternate USB stick. Don't use the existing stick, as it has the files that are needed from the satnav on it. (Preserve what you have).