Hi There,
I am quite skilled updating TomTom systems, but know close to nothing to do so with Garmin systems.
A friend of mine asked me to help him with updating his Nuvi52 Western Europe.

First of all, is this possible?
Can I just copy an unlocked map image and that's it?

I see some maps are marked wit NT and some NTU, or as IMG or Gmap...
What are the differences and which one do I need?

Any help would be appreciated.

BR,
Bootzinker

Bootzinker wrote:.......
First of all, is this possible?

Yes.

Can I just copy an unlocked map image and that's it?

Provided the map *.img file has been properly unlocked with latest gimgunlock (V0.04) it will work because US/EU nuvi 52 doesn't have MSV protection only MAP & GMA protection which gimunlock can overcome.

I see some maps are marked wit NT and some NTU, or as IMG or Gmap...

What are the differences and which one do I need?

NT mapping doesn't fully support unicode use, NTU does. An IMG file is what is used directly on the device. Nuvi 52 uses Europe NTU normally. It can also use NT however there aren't the full ancillary files available for it with EU NT so choose the EU NTU.

.GMAP folders contain all the data to compile a custom *.img file and send it to the device. That's done using Garmin's MapInstall program and it's particularly useful if you don't have sufficient space on-board for the additional mapping as you can choose what parts to install tile by tile. However if you intend to use unlocked maps you'd best put them on a microSD anyway because then if there's any corruption of map data you won't 'brick' the device.

Thanks for your quick and thorough explanation.
Since I'm completely new with Garmin devices, I need some more assistance.
It is a Nuvi 52 Western Europe edition.

How can I tell if the image I downloaded was unlocked with the latest gimgunlock (V0.04)?

First I downloaded the Western Europe NT which contained only the "gmapprom.img,
and later I downloaded the Europe NT file (because it was newer) but this file contatained a lot more subfolders like:
Additional files, Cure, gmap3d, Pc install Locked and Unlocked IMG (which contained gmapsupp.img).

Can I use this bigger Europe NT image, or should I look for the latest NTU image?

The nuvi 52 is a basic device and doesn't support extras such as gmap3d.img which is for 3D Buildings and Landmarks in major cities. It does support JCV (junction view) however requires a file specific to that model range and it's not supplied with the NT version, only with the NTU. My best advice is to use the NTU for whatever region you wish to add, if you already have a W.EU NTU onboard check that the device isn't an LM (lifetime map) edition, some releases of 52 were going from memory.

You can check if an img file is locked by opening it with GMapTool [google for it] and looking at the data behind 'Details' or 'Info' tab and look for this:

Code: Select all

Map              length s-f  CP    prio  PID   FID  name

 I18217BD NT   15738303  1 65001  30       1  7286  EASTERN LONDON, ENGLAND

If there's a gap after "30" under the heading "prio" in every map tile entry as shown above then it's been unlocked.
If you see it like this (L S behind 30), it's locked

Code: Select all

I18217BD NT   15738303  1 65001  30 L S   1  7286  EASTERN LONDON, ENGLAND

Or you can just run gimgunlock V0.04 on it, It doesn't matter how many times a map img is unlocked, it won't damage it. Or just put it on a microSD card named gmapsupp.img in a Garmin folder. If the device shows 'Cannot unlock maps' message then it's locked, but if unlocked it'll show and be selectable in Map Info of settings.

@B1ng0:
Again, many thanks for sharing your knowledge with me.
This was very helpful.