@Giomen: A better question is which JCV file did he download?
@MarianoDC: I have a 1300 and had done this modification some years ago. Junction view does work, but only if you grab the right file. The default file would be about 50MB in size, in the unlikely event that Garmin actually sent the file with the map update. The one you want is the largest file Garmin makes available, over 800MB. It's also the only file that can be downloaded directly from Garmin's servers. Naturally, with the restricted space in the device, it's probably best to put it on the MicroSD card.