Bricked Nuvi 780

**calebrulez** · 31st July 2015, 02:27 PM

The Nuvi 780 kept continuously rebooting as a few files were corrupt. The service center here claimed the board is corrupt but i know it was my fault while carelessly copying files to the device.

I've installed the Garmin drivers, Web Updater and downloaded nuvi7xx_GCDfile__540.gcd in preparation.

Was able to use GarminCure3.exe to successfully load the Cure with nuvi7xx_GCDfile__540.gcd

The file system wasn't getting mounted in Windows so i used RMPREPUSB.exe with default settings listed in thread [Only registered and activated users can see links. ] to format the disk.

Now the Nuvi straight away gets into mass storage mode and i don't get any chance for Updater.exe to load back the original firmware. Am trying:

1. Nüvi is switched off.
2. Press and hold top left or right or both corners of the nüvi screen.
3. While still holding corner of screen, connected nüvi to PC via USB cable.

Have also tried holding power switch, then top left concern then connect to PC or hold power switch, top left corner, lock the power switch and then connect to USB.

Within a few secs it shows up as removable drive in Win 7 (32 & 64 bit). The Updater.exe application does not even momentarily display the device under USB for updating. Garmin Web Updater does not recognize the device even though it's listed as a drive letter.

What can be done to get the Nuvi 780 into pre-boot mode for updating to original firmware again using Updater.exe?

Thanks in advance for guidance on getting this resolved.

**lolypop000** · 31st July 2015, 05:37 PM

Do you install garmin drivers from garmin webpage?

For preboot on your device you must do this:

- turn off device
- add finger in uper left corrner of screen and add buton in lock position
- now with other hand connect device to Pc and nuvi will turn on and updater will see your device

**catymag** · 31st July 2015, 05:55 PM

if you don't succeed try [Only registered and activated users can see links. ] too.

**calebrulez** · 31st July 2015, 06:56 PM

YOU GUYS ARE THE BEST!!!!

Starting the pre-boot sequence with the power switch in lock mode did the trick. I was able to flash to the original firmware (moved the lock mode switch to normal position during flashing) and the Garmin Web Updater identified the device afterwards.

After getting back control, i ran a scan of my Nuvi 780 disk. 25% of the disk is damaged and is most likely what caused the infinite reboot in the first place due to file corruption.

zfytFEh?1

What are my pragmatic options from here. Use an SD Card to store all maps and that way i can extend the use of this device? What would it take to repair the damaged disk?

Thank you so much again for the timely help.

**catymag** · 1st August 2015, 02:04 AM

What are my pragmatic options from here. Use an SD Card to store all maps and that way i can extend the use of this device?

Best option

What would it take to repair the damaged disk?

Device is old, IMHO is not worth to spend money, a refurb. unit would take less.

**calebrulez** · 1st August 2015, 07:20 AM

The voice, xml and other files on the Garmin device take up only ~5MB. So hopefully very less chance of getting corrupted. I've plugged in an old 8GB SD Card and the maps load like a charm. This combo works for me.

Thanks again for everything!

**Giomen** · 2nd August 2015, 01:33 AM

Originally Posted by calebrulez

After getting back control, i ran a scan of my Nuvi 780 disk. 25% of the disk is damaged and is most likely what caused the infinite reboot in the first place due to file corruption.

It may be false alarm. What SW version was on device before bug? SW version of 5.30 was very buggy. It wrote the corrupted current.gpx file and after this file was about 2Mb size the system crashed due to file system bug. After deleting of GPX folder and reboot with new SW update of 5.40 device worked fine.

**calebrulez** · 2nd August 2015, 05:03 PM

Am on SW version 5.40.

The whole infinite reboot issue started when I updated to a large map (which most likely got copied in a corrupt state).

Am getting disk errors reported by Windows Scandisk, Norton Disk Doctor and HD Tune. Have also seen files get corrupted on the drive and Found.000 folder(s) being created. All point to classic symptoms of bad sectors.