Quote Originally Posted by tiger555 View Post
One more thing... If you have multiple versions of a map installed, enable only one at a time. Otherwise, they will not work correctly. For example, if you have both "CNNA 2012.1" and "CNNA 2013.2" installed, select only one at a time because they cover overlapping geographical areas.
Quote Originally Posted by FireFox58 View Post
I think this occurs automatically, personally verified with CNEU NT. If you mount a more recent version of the same Map (same Map family), this one overlay the older one, for the corrisponding coverages
Although not really recommended, if it's the same map series the overlapping info usually isn't a problem even if the versions do differ. Last year i spent several weeks in northern NA, mostly in Wisconsin and other States bordering CA. Using an AU1350 with USA Lower 49 2012.20 and CA 2012.10 (which included the US northern border states) loaded on a microSD and didn't realise until later that both maps had been checked as selected on the unit (i blame my un-gps-savvy travelling companion for that). It does beg the question of what might have happened if we had just chanced to be some exact place where the map data had been updated in the 2012.20. If the unit was getting conflicting info from both maps, would the later version have 'automatically' overriden the older one because it's 'overlaying' it, as FireFox58 thinks, or could the nuvi have had a 'hissy fit'? Probably not something you want to find out in the negative if you're in the middle of an unfamiliar city during peak-hour or negotiating a busy freeway interchange. The safest policy would be, don't select both if you have maps overlapping and their IDs differ as it's pointless anyway. If both have the same version and family it doesn't matter at all.