2013-4 JCV

PS, approx 100MB remaining on the 855

Correct, the nuvi 855 will not be offered the large jcv file by default. It needs to be manually downloaded and copied. My preference is to put the large jcv file on a SD card and renaming the small default jcv file D.........0A.jcv.disabled. Just remember that a .disabled file will remain on the nuvi after the next map update so you'll need to delete it manually.

Check this link (keeping in mind that map version and jcv file names will be different now and for the next map update):

http://www.poi-factory.com/node/34056

and look for the 8/12/11 8:56PM post with the Subject:

In a nutshell (OK, a large nutshell),

particularly paying attention to Step 5.

Good luck and have fun. I expect your method will not have sufficient room in a soon-to-come map update, possibly even the next update. I also suggest waiting to update a 855 map until we know the large jcv file is available--I usually download the large jcv to my computer before starting the map update.

Thanks Craig - always get the large file before I start anything - has usually worked fine with ethe JCV on the SD, but, s..t happens, right?

I've got the link bookmarked - lots of useful info there.

Regards,

DougJ

I keep hearing that very soon the map file will be much larger. What's the basis for this speculation?

Really? well how about the 3590 or 3790?
Neither of these get the large JCV by default.
Which units get them by default then?

Speed2, I guess it depends on how you define "large JCV file". The 3590 and 3790 do get the appropriate full coverage JCV file for split screen display. It is true that this file is smaller in MB than the full screen version referred to by CraigW, but it should have the same coverage of intersections included in the data. The 7x5 nuvi series and some Zumo's get the large full screen file by default.

The main use for the large jcv file is the older nuvi models that display JVs. This includes, I think, the 8x5, and maybe some of the 1xxx models that use full-screen JVs but are space-limited which may be the reason Garmin offers the tiny full-screen jcv file by default.

I believe all the nuvi models that display split-screen JVs receive the proper jcv file by default during a map update. Note that the "proper" jcv file for split-screen nuvis is around 400MB in size since images contain fewer pixels than those for full-screen displays.

There is an important but fairly small minority of owners of split-screen nuvis that prefer the full screen JV display--and for these folks, they will need to manually download and install the large jcv file. But most split-screen owners prefer the split-screen display and therefore they need do nothing special during a map update.

But then, I somehow think you already knew all this

For folks with a split-screen-enabled nuvi who want to try the large 750-ishMB large jcv file, I strongly suggest keeping the original 400ishMB file since a moderate to large majority of split-screen nuvi owners who try the full screen large jcv will decide to return to split screen.

I'm not sure I want to buy that. If I update both units normally they will both get the same size jcv file. The 3590 for Junction view has (photoReal and Bird's Eye views) The 3790 does not. I would think that the 3590 should have a larger JCV file, but maybe not.

I have no device that shows Birdseye views. Isn't it possible or likely that birdseye views are kept in a different file than the standard JCV file?

Does your 3590 show a Garmin/BirdsEye folder? The file naming structure may be different for nuvis but can you check your 3590 and see if you have an .jnx files? For some non-nuvi Garmin devices that offer Birdseye, I see some discussion of jnx files. Assuming the 3590 has a system folder called ".system," make sure your folder options on your computer are set to show system files and that the GPS is in mass storage mode rather than MTP if that's needed as well before looking for a Birdseye file or folder.

Or...we could just wait until someone pipes in who already knows the answer to this.

It never has been, to my knowledge - always have to download it separately. My original question was why do I keep seeing reference(s) to larger map files? Is it the JCV that they're referring to?

In addition to size increases in the JCV file, the map .img files grow in size from update to update. It is not uncommon for a map file to be 50 MB or more larger than the previous version. I assume the map file grows because of added roads, increased coverage of lane assist data and speed limit data, new POI's, etc. While an added 50 MB doesn't sound like a lot for a 2 GB file, over many updates it adds up to several hundred MB. And sooner or later, the older nuvi's like the 8x5 series run out of space.