joelton12345 wrote:no, what I mean was if I move the MSM map to sd card, should I move the junction view files together? what is the junction view files name? will cause junction view malfunction？
JCV files are coupled with the maps and must be moved together. If your set is a localized set, then you will have 2 preloaded maps (gmapprom.img and gmapprom1.img) in your \.System folder in the internal memory and 2 JCV files in the JCV subfolder of the \.System folder.
You can move the 2 maps to your SD card and put them in a \Map folder and the maps will work even without any name change.
But for JCV to work, from my experience, the map must be in the SD card's \Garmin folder (and not \Map folder) and the correct JCV file in a \JCV subfolder of the \Garmin folder in the SD card.
Your problem is identifying which JCV file goes with which map. To overcome the problem I put all JCV files in the \JCV subfolder regardless of which map I am using. The only downside is that they take up some space. Garmin usually names each release of JCV file differently from the previous so unless you know which file is for which map, your JCV subfolder may contain a lot of orphaned JCV files.One very important consideration.
If you move the map to the \Garmin folder, for it to work, the map must be renamed to gmapsupp.img
. Your problem is knowing which map is the one you want in order to rename it.