It is not something that the dealer can just lock it is 8.4A or 8.4AN the N stands for Nav and is actually a different system that allowes 3d maps where just the 8.4A does not. The dealer can download the Nav from Chrysler but it does cost ~$600 that is not up charged from the dealer. You can just not use it if you do not want to and now with the Drag and Drop Feature you can just take it off the menu bar so you do not see it.With the 8.4" uConnect they all come with nav in the software. It is a dealer unlocked feature so it is up to the dealer if they unlock it or not. If they can unlock it they might be able to lock it again and then you save.
Plus if you get the 8.4AN you get a 12 month subscription to U Connect which is worth it to me.