Guys...I’m struggling with updating to the latest version of map on my 3770.

I gone to the website and found two files....CDG-MAP Dual Nt V.11.1 (231MB) and Junction View TSM 11.1 (230MB)

My installed maps are..Thailand DEM...Thailand Street Map V11 NT 3D and Thailand Street Map V11 NT (Dual) ALL

I now look in my Garmin folder and only find one file..Garmin Device.

Can someone advise which files to download and where to put them..I have already exported a file call Current.gpx which I hope is the favourites file

1. The actual map and junction view files are hidden by default in the .System folder. "In Windows Explorer, go to Tools > Folder options... > View and click select "Show hidden files, folders, and drives" and remove the check mark in front of "Hide protected operating system files (Recommended)". The .system folder is now visible."

2. For the TSM 11.1 you just copy the map and junction view files to replace the same file in your unit.

3. Current.GPX is the favorites file and needs to be saved to your computer before updating firmware.

Edited July 31, 201114 yr by InterestedObserver

1. The actual map and junction view files are hidden by default in the .System folder. "In Windows Explorer, go to Tools > Folder options... > View and click select "Show hidden files, folders, and drives" and remove the check mark in front of "Hide protected operating system files (Recommended)". The .system folder is now visible."

2. For the TSM 11.1 you just copy the map and junction view files to replace the same file in your unit.

3. Current.GPX is the favorites file and needs to be saved to your computer before updating firmware.

I only see one big file..but the new files are both about 230MB...so I download those two and copy over the disk image files? thanks

Edited July 31, 201114 yr by JAS21

I only see one big file..but the new files are both about 230MB...so I download those two and copy over the disk image files? thanks

The map is the approximately 230MB gmapprom disk image file and the junction view is in the JCV file folder. They should both show a current "Date Modified" after updating to version 11.1.

Edited July 31, 201114 yr by InterestedObserver

Thanks IO your posts are most informative.

The gmapprom file was no problem.

However I did have a little problem with the JCV file update. I contacted Garmin and the guy (K.Banyong) was very helpful....it needed two of his replies to sort me!

The detail instruction he finally gave were...

For the JCV file, please follow the instruction below:

•Delete the JCV folder in your nuvi (if you still have it)...I had already done this.

•Unzip the downloaded JCV file on your PC

•Copy the .exe file onto your desktop

•Double click this file (from the desktop)

•When the program asks for the destination, select the nuvi drive (which is connected to your computer)

•The installation program will create a new JCV folder and copy the junction view file onto your nuvi device under this folder.

It's up and working...well I think it is.. so I am happy..........his suggestion about updating firmware was....

If you haven’t encountered any problem with the unit, you don’t have to update the firmware. The new firmware 2.20 is for the units that experience rebooting issue (keep rebooting at certain locations when navigating).

I just posted incase it helps anyone else.