Thread: GPSMAP 78s

so, i have gone over this again and again trying to find some detail you as a techie would need, i can only offer a couple things:
1) email sent to garmin support when this started 19-nov-2024:

Trying to install maps form MAp Installer Topo software and now unit is corrupt - it wont stay connected via USB anymore and after trying many cable/PC combinations no luck. It needs to have batteries removed after powering down before powering up. Master rest also doesnt work

How can I force a firmware update not using Express/Updater - neither of those programs work since USB connectivity wont stay up long enough to allow software to update firmware.

2) i have tried copying the files off more than 1x - never could get the unit t connect to laptop long enough and stable enough to get a copy - my 1st thought when this started happening was the nuclear option of a format and rebuild it...

3) between trying to fix this winter of 2025 and now - i had batteries pulled out of it... in winter 2025 i decided i was down to option of shipping away at cost of $$$ to ry and recover it, so prepped for mail on my desk with no batteries... when i figured i would make 1 last attempt it was after a number of months with no batteries after it started acting odd...

i going to have another go at this, but i did notice that the gmapsupp file large when compared to my other devices - as on the 100mb to GB range...

do you have any idea why this happened - or jut a bad chip or 1 of those things that happen?