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#1 2017-01-04 19:30:25

Registered: 2017-01-04
Posts: 1

Garmin help please. Europe maps load but not custom bbbike maps


I have a garmin echomap 43dv and want to add marine maps. The pre-made Europe maps from this site load fine and work great but sadly I don't live there. I've tried to make custom maps of the US east coast following the link to but unfortunately those fail to load. I get an error, "The map file is not supported."

The file is not large (smaller than the northern Europe one I tested). I have tried both UTF-8 and ASCII Garmin OpenSeaMap format and neither works. I really hope someone can help me. Thanks in advance!


#2 2017-04-20 12:45:30

Registered: 2017-04-20
Posts: 1

Re: Garmin help please. Europe maps load but not custom bbbike maps


I have excatly the same problem with my Garmin GPSMAP 547.


#3 2017-06-15 19:36:11

Registered: 2017-06-14
Posts: 3

Re: Garmin help please. Europe maps load but not custom bbbike maps

Try copying the file , e.g. gmapsupp.img to a clean SD card and try Basecamp or Homeport these Garmin programs will read the chart from the SD card, the chart should open either the UTF-8 or ASCII formats. This will enable you to 'view' the chart. You can add multiple charts to the SD card, just rename the file e.g. gmapsup1.img, gmapsup2.img, the filename just needs to be unique with the suffix .img. .

I have found with the Garmin Fenix 5X watch that charts from need to be ASCII format for the Garmin device to open it without reporting 'Cannot authenticate map'. I copy the file , e.g. as gmapsup3.img to the Garmin folder then restart the device,  enable the chart then 'go' to that area, and it appears.


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