IMPORTANT! If you want HELP in case of a bricked Garmin device, please follow this

I respect your decision and appreciate your sentiments and stating that the effort was "beyond the call of duty". I of course want to help you however there's a slightly selfish motivation as well because i can often learn something out of these 'unusual' brickings. On probability, it's likely a hardware problem anyway.

If you want to try erasing the nonvol without examining the firmware BINs you can simply change the update.txt file to read:

ergn,41
reboot

That'll completely vacate region 41 if successful and it'll stay that way until the device reboots, if ever, when the device itself will re-write fresh data but only partially restore it. If the source of the problem is poisoned nonvol data it will in fact boot successfully or at least boot far enough that Cure fw can be properly used.

BTW, your concern about the 14 & 127 bin files is understandable but entirely wrong. There's absolutely nothing personal or individual in those files which can be used by anyone else - nothing more that can be found in general info by examining the BIN components from a firmware GCD or RGN file for sure. I hate to tell you, but it's data in 41.bin that can disclose personal and device info, if a malintent had the ability to decrypt it and know what and where to look for in the jungle of the clear data. Very few ppl do know, outside Garmin itself, i can assure you. Have a look back at your [Only registered and activated users can see links. Click Here To Register...], you'll see i removed the attachment immediately after i downloaded it to negate any chance of someone else getting their hands on it. As a Mod, i could see that i was the first and only downloader. I'll also remove the copy of it from my PC as well, not that i'd ever try to misuse it. Good luck and thanks for hanging in there thus far.

Garmin Fleet 780. I need help with my bricked Garmin Fleet 780. It was working perfectly fine before I decided to update the system via Wi-Fi.
After the reboot, the device entered the system update mode. The file was downloaded, and the installation process started, but it froze. I waited for about an hour, but it remained stuck. I then decided to turn off the device by holding the power button. Upon restarting, the installation process automatically began again, but it got stuck once more. I turned it off again, and after the reboot, I only saw the "Garmin" logo. The device is now bricked. After restarting, the "Garmin" logo is the only thing I can see.
My PC doesn't recognize the device when connected via USB, even though I have installed the Garmin USB drivers. I cannot enter preboot mode. Since the Fleet 780 is Android-based, I'm unsure if it even has a preboot mode

@zserv
Unfortunately, there's no known way to 'cure' Android firmware for Garmin devices. Your best approach might be to throw yourself on the tender mercies of Garmin service desk drones. If you get the run-around ask for it to be escalated to a supervisor due to it having been soft-bricked by their software using their own proscribed method. You might get lucky with an even-exchange replacement as it's most likely out of warranty.

I have a bricked Nuvi 1390 LMT which I'm 90% sure has a bad EEPROM, but I've continued to play with it. It bricked in Jan2025 at the end of the latest map update, when it stayed at the Garmin logo. I've tried:
- QuickCure3 (loads successfully, but no mass storage seen)
- GarminCure3 (won't load, get the white Updater popup saying 'could not program requested memory region, contact Garmin...')
- GarminCure3 with only boot.ini (loads successfully)

I've tried the above many times on three different PCs, all Win10 or Win11. Also tried different cables. The unit USB connector looks OK. My unit uses the same RGN file as in the posts below.

Most recently I tried the SD card-based FW approach in the thread:
"IMPORTANT! If you want HELP in case of a bricked Garmin device, please follow this", post #357.

I got a somewhat similar result to 'askelly' (a green bar, though no logo), and it went thru 'loader' and some other screens before it stayed on 'software loading' until I powered it off (after >15min).

Of note here is that a 4Mb copy of region 41 ('41.bin') was dumped to the SD card, along with an update.log file (text below) and a small 'last_id.bin' file. This may help us nail down how to tell if the HW is bad vs. a soft error of some sort.

Thanks!

update.log content:
nüvi 13xx Series Software Version 6.30, UID: 38(...), HWID: 38(...)
------------------------------------------------------------------------------
Parsing "del,0:/.System/gupdate.gcd"
Success
Parsing "rrgn,41,1:/41.bin"
Success
Parsing "xrgn,14,1:/14.bin"
Error
Parsing "xrgn,127,1:/127.bin"
Error
Parsing "reboot"

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1) Bricked device MODEL, Firmware version, HWID.
Nuvi 30, V3.7, 1349
2) Why and how the device got bricked.
It is not necessarily bricked, it is rather resetting to the default file system upon a reboot. If I try to update it either through Express or manually with a GCD file, the file gets erased after a reboot. I tried deleting the onboard gmapprom to put my own custom one onboard, but my custom one was gone and the default gmapprom was put back. Even system settings won't save after a reboot, I have no clue what to do. I got the device used and first noticed the issue when it wouldn't properly update
3) Symptoms: what's wrong in your device?
What I said in 2
4) Does your pc sees your device ?
Yes
5) List all the procedures you already tried to unbrick it and their results and errors messages obtained.
I have tried factory resets, messing with some developer options but even changing dev options (like turning on demo mode) don't save through a reboot.
6) Do you have Garmin USB Drivers installed ?
Yes
8) Write down if you already read and tried everything in these two threads: GarminCure3 tool - the new way to create cure firmwares for Garmin devices and How to unbrick a nüvi - step by step guide
I'm wondering if I should go through the process of GarminCure3 to reflash it, looking for advice as I am quite a newbie here.
Any help would be appreciated :)

@nsPerFoot
Assuming there really was a file named gupdate.gcd in the Garmin folder before you used the SD card, it seems to have been deleted according to the update.log file. However, my strong suspicion is that the device's internal regions can only be read but not written to. That's backed up by your unsuccessful experience trying to flash Cure3 firmware which is intended to be written to region 14. QuickCure on the other hand is universal and is not firmware dependent, in fact it doesn't involve a device's firmware in any way at all. Similarly, the attempt to flash the 14.bin and 127.bin failed.

I think almost certainly that you're correct, it has a failing flash chip and it will eventually die completely. As you're likely already aware, it's exhibiting much the same symptoms that a bad media card does, i.e. it doesn't save files written to it and deleted files simply re-appear.

@Zakk
Unfortunately it seems your nuvi 30's flash chip is also failing, it just has somewhat different symptoms from those of the previous poster's.

Thanks Neil. Bootloaders were one of the most problematic systems in my work. A microprocessor or controller would use a simple ROM-based loader to open a memory path from whatever interface we used to an EEPROM device, which we then loaded using either JTAG or homegrown SW. We'd often get unrecoverable errors and despite the designers saying 'just reload the FW...' usually it was off to the rework dept for a new EEPROM. Our hi-rel designs thus often had double-or triple-redundant EEPROMs.

On the off chance I can do a chip rework, is your SD card process sufficient to reload the necessary FW to a new EEPROM to at least get me back to GarminCure3? Also, if anybody has the P/N for the nuvi 1390 EEPROM chip, let me know. I'd try this just for the challenge of it. Our new chips always came already 'balled' so it may be possible, if the chip is still available.

Ah, i see you have solid knowledge of EEPROM workings - in fact far more than i have at granular level given your professional background. Garmin is a queer fish at best and a very closed one at that. It's easy enough to replace the EEPROM physically, it's a common chip i believe and you can swap 13/14xx between other series, such as using a doner unsweated from old 2xx/7xx PCBs with reballing. I've also heard that a simple everyday media card like a small microSD can be micro-soldered in with jumper wires if you know the correct corresponding pinouts. The problem then comes in re-programming the replacement, i have no idea how to do that but unfortunately, it's certainly not as simple as re-loading fw, whether by the SD card process with individual bin files or by loading an RGN file using updater.exe. There were some very skilled users on this and other forums who did know and who had access to the necessary equipment to do such stuff, but they all seem to have disappeared these days. Sorry. I think that with older Garmin devices being so very cheap now that it'd be impractical to pay someone to re-program it anyway but its other individual parts like screen, battery, USB socket (it's a less-common type) and case components like the bezel have some value sold as spare parts anyway. There's still active selling on e-flea for such bits.

yes there was discussion in #357 section I do agree below mention also having Parsing "del,0:/.System/gupdate.gcd"
Success
Parsing "rrgn,41,1:/41.bin"
Success
Parsing "xrgn,14,1:/14.bin"

was able to get the first one cleared and check it tomorrow is there any difference in update code

I took the my 1390 apart and pried off the PCB's metal EMI shields. The 'logic' side of the PCB has an ARM microcontroller seemingly customized by Garmin, a Samsung 2GB flash memory, and a Bluetooth IC. The other 'analog' side has some GPS and analog amplifier ICs. The Samsung IC is basically a solder-in MMC memory card, which likely makes use of a standard MMC interface in the ARM chip. Most custom ARM chips contain both factory-programmed ROM (not editable) and some flash memory.
My guess is that Garmin has a custom hard-coded loader burned onto their IC, and that in turn loads other FW from a GCD file or similar via the USB port. I couldn't find any obvious PCB pads that supported board-level programming. In my experience we always programmed all flash memory when a product was fully built up, since this allowed for serialization and avoided having to manage multiple versions of commonly-used chips. So, if all Garmin FW lived in the Samsung flash IC, then replacing that and executing the cure process might work. However, if the ARM's onboard flash is also used, then that could be the issue and that chip would also have to be replaced. Both ICs are available from overseas surplus electronics wholesalers, but I decided that life is too short in this case. Flash is usually good for 100k+ write cycles, but is easily damaged by the type of environments seen by our automotive GPS units, such as starting your car with the GPS plugged in, unplugging it from a PC without 'ejecting' it first, and so on. Garmin might also write to the flash during normal operation, which would wear it out after ??? hrs of use. 15 years isn't bad. I guess I'll baby my eTrex 20 going forward!

Spoiler: images

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