855 JCV

D3060030A is meant for 2012.20. This is the correct Junction view file for the latest map update:
http://download.garmin.com/support/2012_30/NA/JV/D3060040A.J...

You must ALWAYS use the JCV file that corresponds with the map you are using. Using an older version will NOT work.

The file you need is 775MB (D3060040A), the link that rame2012 posted no longer works.

Perhaps since it's such a large file you don't have sufficient internal memory, and that's why it didn't download.

Thanks for that link and I have a question:

I've seen multiple references here to the opportunity to place the junction view file on an SD card, thereby leaving plenty of memory available on small memory devices such as the 855. My wish is for slightly more explicit directions on doing this.

1. First regarding the SD card, anything special about clearing it and formatting it before use, and if one formats it for example, while connected by a card reader to a Windows machine, which format should one use?
2. Second still regarding the SD card, should one place anything besides this JCV file, and in particular should one place the JCV file in a subdirectory or at the root?
3. Should one simply delete the JCV file that came in the update from storage on the new the Nuvi? In Windows I presume one should use shift-delete to avoid placing it in the recycle bin of the Nuvi storage and thus wasting space?

Thanks for any help. I've enjoyed using the full size JCV file for the last five months on my 855, but would like to shift to the SD card method so that I have plenty of space, rather than needing to look for things to delete and fretting about little headroom.

Check this link:

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 (remembering to use the new 2012.30 jcv file, not the one described at the time for the 2012.20 map). You want the D.....40A.jcv file, not the D....30A.jcv file.

Good luck and have fun with the large number of JVs soon to appear on your SD card!

I succeeded. I used a new, slow, small Kingston 2GB microSD card. Attaching it to a card reader, I used Windows 7 to do a full (not quick) format to FAT32 with 4096 byte cluster size (took about ten minutes). I created from the root of the card the directories /garmin/jcv, then copied to the new SD jcv directory the large file pointed to by so many posts.

As the pointed to post suggested, I went through normal map installation, then used Windows Explorer to delete the (roughly 45 Megabyte) .jcv file that left in the garmin/jcv directory of my 855. I then disconnected the 855, powered down, removed the battery, installed the SD card, installed battery, booted 855, and tested by turning on the simulator and simulating a route involving an interstate interchange. A high-resolution junction view was present, which could only have come from my SD card.

But... there was a large bump in the road on the way in my particular case--not likely to happen to others, but I'll tell the tale in case it might help.

Oddly, my attempt to follow the prudent backup directions got me to a frightening spot I've not seen before. In the midst of copying the large (~750 Megabyte) .asr file, Windows advised me of error, claiming it wanted me to install media of a certain name. Trying to cancel just left me with over ten minutes of "...cancellling", and shutting everything down and then trying to shut down the PC left the PC hung up in the shut-down sequence. Finally I held down the PC power button the requisite 5 seconds to get to power off, then had to go through abnormal startup for both the PC and the (now unplugged) Garmin. The Garmin gave me "kernel error" on being turned on, which I've never seen before. Happily it responded to the classic 855 forced reboot technique of holding the power "suggestion switch" left for ten seconds, and after that all was well. I don't know what happened, but mention this in case others might see it.