Jul 31, 2013

Garmin Nüvi map files

Here are the Garmin NUVI Map File Naming Conventions:

  • gmapprom.img - primary mapset, factory installed USA or Europe or other country.
  • gmapprom1.img - secondary mapset, example: North American / European units
  • gmapsupp.img - supplemental mapset, located on the Nuvi drive
  • gmapsupp.img - supplemental mapset, located on the SD card
  • gmapoem.img -  OEM mapset, user accessible, cannot be unselected from the unit via Tools/Settings/Map/Map Info
    *Note, when using the following default system maps as user maps, you'll naturally lose their default map attributes.
  • gmapbmap.img - default basemap, configurable as a supplemental map; NOT selectable and does NOT show up under installed maps (Tools/Settings/Map/Map Info) but may be visible under Tools/Settings/System/About/Basemap
  • gmaptz.img - Timezone map, configurable as a supplemental map
  • gmap3d.img - 3D Buildings map, configurable as a supplemental map
  • gmap3d1.img - secondary 3D Buildings map, configurable as a supplemental map
Now, if you're wondering which files to delete from your Nuvi drive or SD card to clear up some space, this should provide some insight.

You can easily remove/replace the primary, secondary or supplemental mapset, however you should keep the timezone map. Basemap can be deleted, however it's only around 50 MB in size.

With an SD card in the Nuvi you can fit around 4 custom maps, with the following naming conventions: gmapprom.img, gmapsupp.img. You can even use gmapbmap.img, but note that it will not be selectable from the settings.

Maps on the SD card are located in the folder Garmin.
Maps on the Nuvi drive are located in the .System folder (with a dot) or in the Map folder.

If you can't see the .System folder, you might need to change the USB mode on the Nuvi from MTP to mass storage.

You can get free maps for Garmin from OpenStreetMaps:

or from Open MTB maps (Mountanbike and Hiking):

Garmin Nüvi connected as media device - disable MTP, enable mass storage

What is MTP mode and which automotive devices use it?

Some automotive devices use Media Transfer Protocol (MTP) for connecting to your computer. MTP provides a more secure environment for the important system files on your device.
MTP connectivity requires the following:
  • Windows XP with service pack 3 or later
  • Windows Media Player 11 or later
The following devices use MTP  mode:
  • dezl 760
  • nuvi 2405 series
  • nuvi 2407 series
  • nuvi 2408 series
  • nuvi 2505 series
  • nuvi 2507 series
  • nuvi 2508 series
  • nuvi 2707 series
  • nuvi 2708 series
  • nuvi 3400 series
  • nuvi 3500 series
  • nuvi 3507 series
  • nuvi 3508 series
  • RV 760
  • zumo 350
If the above system requirements are not met, or you are using the device on a Mac, the device will connect to the computer using standard mass storage mode instead of MTP mode.
Make NUVI DIR & Files visible for Backup

1. To make all of Nuvi files visible you must unhide protected files via Win7 like any other HD.
2. Start NUVI by itself and go to Volume Screen.
3. Press the upper right hand corner of screen for 10 seconds.
4. The Developers Screen will pop up
5. Scroll down to MTP SETTINGS
7. Shut down NUVI and hookup to Computer USB cable
8. Start NUVI and it should recognize it is hooked up to the computer.
9. Explorer will now see all files in ROOT directory and the .System directories.

BTW, have you backed up your Nuvi? If not, then this would be a good time to do it. Could save a lot of grief later if you have a problem.