Junction view on SD Card

If I'm understanding your situation, you have an older version of City Navigator North America with its Junction View file and other features on your 1450's internal storage AND you have a newer version of City Navigator on your SD card.

I don't think I've heard it asked before if it's possible to switch from one to the other while maintaining features like Junction View so it'll be interesting to see how things work out. My fear is that there may be a problem with Junction View. Have you tried driving or simulating a route with Junction Views with each map? If so, do you get Junction Views shown with one, the other, or both maps?

This may be related to how you did your most recent map update. I'm assuming that you didn't simply do the map update with Garmin Express or GarminMapUpdater to the SD card since that should have erased the older map on the nuvi. Did you use the clone method suggested by alandb or something else?

http://www.poi-factory.com/node/39231

In any event, I expect the Junction View file you have for each map (they are different and each will only work with its intended map version) is the small one that Garmin offers to the nuvi 1450. In each case, the large JCV file (full-screen, photorealistic, and about 775MB in size) can be used in place of the default jcv file that came with the update--although each version of City Navigator requires a different large JCV file.

But I do fear that having two JCV files and expecting the nuvi to switch from one to the other is not going to work. You could work on proving me wrong, though.

With a single map, I believe the JCV file can either be installed to the nuvi or to the SD card.

I have no thoughts on the 3D building view issue since I have no unit that uses or displays them.

Is there a reason why you want to keep the old map, especially if it may cause possible problems showing Junction Views?

Let's hope someone has first-hand experience with your situation and can offer better advice.

Nuvi's, at least the ones I own, 13xx, 2xxx series, work with multiple JCV files present at the same time, one each corresponding to the maps installed.

The map and the corresponding JCV do not have to be on the same storage device, e.g., the map can be on the internal storage and the JCV on the SD card.

Installed on the SD card, the JCV needs to be in the \Garmin\JCV directory.

Other directories might work. I think \.system\jcv directory works too. Experiment with them to find out if you are game.

Good to know.

I was always under the impression only 1 JCV file would b recognized by the Nuvi.

I may be wrong on this, I thought if two maps were installed of the SAME AREA, one on the unit, the other on an SD card, only the newer map would appear in Map Info so disabling the older map would not be an option. I'm curious to know if two JCV files were installed, is the Nuvi capable of determining which JCV file goes with the proper map.

The plot thickens.

The new map would look for the corresponding JCV file and ignore JCV files linked to older maps. You should be able to have 2013.40, its JCV file, and 2014.10 and its JCV file on the device at the same time with no ill effects.

Thanks muell for your input. if you look your gps main directory you will find a file called:GMAPPROM.that is the map on your device ,if you install a map on the SD card then you will name it GMAPSUPP. the you select tools map/info and it will display 2 map the one on the Garmin unit and the one on the SD card, and there you have the option to select the map that you wish to use by removing the " check mark" on the one you do not want to use.the JVC file yes must match the map version that you have I found it here by clicking on a link and from there i was able to download the JVC. the file was over 700 mb, most JVC file they look ammazing especialy if you drive in a big city like NY.So some people in here they may have it already but they never see it yet.

Thank you Strephon for the information.
YOU Can have two maps of the same area appear on the Map info page at once. I experimented and copied the 2013.40 map to an SD card and had the 2014.10 on the unit. They both appeared in the map info page.
Good to hear the Nuvi will determine what JCV file goes with which map.

By doing this experiment I learned my backup method on the Nuvi falls short if wanting to install older backup maps. Backing up the gmapprom.img, xxxx.JCV, gmapprom.unl, and gmapprom.gma will get the map working properly, however TWO additional files need to be backed up for voice command which I neglected to do.

For those members that have a voice activated Nuvi, YOU MUST also backup the two files in the .system\ASR folder. They end in .ASR and .SRX.
These files are required for voice activation and change with each map update.

I only have one map at a time on my Garmins and the map is always on the unit. Garmin thinks my 885t doesn't have the space for the large file, however, so I always get the little one with each new map. So I delete it and move the big JCV file from my 765t to my 885t's SD card. I have to eliminate the little one and put the file on the SD in the same diretory structure as the file was on the nuvi. Works fine.