Installed TOPO US 24K Southwest on GPSmap 78 not displaying any topo lines

Former Member over 4 years ago

I purchased the GPS used. The prior owner loaded several maps but none seemed to work (I believe he copied from another GPS so they were locked). I purchased Garmin's TOPO US 24K Southwest, and (maybe was s mistake), deleted all prior maps from the GPS using my computer, thinking this was required for the new map to work. Now, on the GPS, there will be a few topo type lines but nothing usable, and the screen is primarily void of any map at all (also very slow when navigating through the map). When connected to computer and using Basecamp, the topo map (when selected) looks identical to the default global map contained within Basecamp, no topography.

Did I make the mistake of deleting the basemap that other maps rely on causing the issues with the topo display? I also see that the topo map may need to be activated? I paid and downloaded per Garmin Express prompts so not sure how to unlock beyond what I've already done.

Thank you anyone who can shed some light on this issue!!

0 SUSSAMB over 4 years ago

Let's take this one step at a time. You say you deleted the basemap? How do you know? The basemap on the device is named gmapbmap.img and will be in the Garmin folder. Using Windows explorer does it show? If so then it's there, if not your device will work without it.

What other files ending with .img are in the Garmin folder?

0 Former Member over 4 years ago in reply to SUSSAMB

Thank you for the reply. How do I know I deleted the basemap. While the GPS was linked to the computer, I deleted all files under Garmin, on both the GPS and the microSD card. I don't see any gmapbmap.img listed, in fact, when searching for that file there are no results. All I can see are GPX and BIN files. I really can't even see the new Topo map I had just installed.

0 atlas_cached over 4 years ago in reply to Former Member

Sounds like you destroyed all the map data (and other data) on the GPSMAP 78.

Not sure why anyone would do that.

You may be able to download the TOPO map you paid for again, and this would be a good starting point, but without the basemap, it may not function as expected.

And Garmin is not known for supplying basemaps to those who have delete them... If you can find another user with a similar device, you can copy the basemap from one device to the other. Basemaps are not locked.