Maybe the nüvi 1300 uses some default legacy garbage in the firmware that is just empty placeholders from the past?
Looks that way if you have tried gmapsup2.img and also internal vs. memory card storage.

Some of the terms from a GarminDevice.xml file:
  • PreProgrammedMaps
    1. gmapprom.img
    2. gmapprom1.img
  • SupplementalMaps
    1. gmapsupp.img
    2. gmapsup2.img
  • BaseMaps
    • gmapbmap.img
  • TimeZoneMaps
    • gmaptz.img
  • PreProgrammed3DMaps
    1. gmap3d.img
    2. gmap3d1.img
  • Supplemental3DMaps
    • [GPS or memory card]:\Map\any_name.img
  • PreProgrammedDEMMaps
    • gmapdem.img
  • SupplementalDEMMaps
    • gmapdem1.img


OEM data in gmapoem.img is usually some very small files with branded data for dealer POIs.
Some examples of gmapoem.img files from Garmin or branded Garmin units:
[Only registered and activated users can see links. ]
[Only registered and activated users can see links. ]
[Only registered and activated users can see links. ]
[Only registered and activated users can see links. ]

There's similar gmapoem.img files for branded versions of units sold by Tesco, Dixons, Carrefour, Géant, Hyundai etc.

More about the map files here:
[Only registered and activated users can see links. ]



This post suggests that Suppmap1 is the internal gmapsupp.img and that Suppmap is the gmapsupp.img stored on a memory card. That's for nüvi 7x0 & 7x5.

Quote Originally Posted by catymag View Post
Multi maps on Nuvi 7x0/7x5

original poster hulio (thanks)



Nuvi internal (diagnostic utility) OS map naming
-----------------------------------------------------------
7x0/7x5

1. PROM1 = gmapprom.img
2. PROM2 = gmapprom1.img
3. Suppmap1 = gmapsupp.img (nuvi drive only)
4. Suppmap = gmapsupp.img (SD Card drive only)
5. Dir DB = gmapoem.img
6. Basemap = gmapbmap.img

7x5 only

7. TZMap = gmaptz.img
8. 3DMap 1 = gmap3d.img
+9. 3DMap 2 = gmap3d1.img

About the 4 GiB barrier!

Well, you can put as many <= 4 GiB map files as you want in the Map directory of your memory card. As long as there's room for all the files anyway.
The problem is other constraints like how many map tiles your unit supports and the most severe constraint about the number of map families it can support.
If I store all TOPO Norway Adventure in one gmapsupp.img then I have 20 map families there. That's NOT readable by any Garmin unit I've tested including the Garmin Montana 650t. Normally it works with 16 or 17 MapIDs as the total for all maps but not with 20.