Quote Originally Posted by jamesbxue View Post
Yes I used RMPrepUSB, following the setting in the "unbrick step by step guide." It looks like have been completed successfully. Right after formatting I think I saw only one folder called something like "formatted drive... ". Then after Garmin Express software refresh (I only got through halfway stopping at the restart), I think I saw 4-5 folders.
Then certainly the format was correctly done. It seems GarminExpress has loaded something which again this device finds disagreeable although this time it is indeed soft-bricked. As to what that is and why it's 'bricking' the device is impossible to know without loading cure firmware to restore M.S.M., remove existing files or reformat yet again but almost certainly it seems GE will yet again load something that the device is unable to deal with. This is an unusual situation, not what any healthy device will do after updating with new files directly from the Garmin servers following a format.

No I don't have Mass Storage Mode anymore at this moment. I had Mass Storage Mode after the formatting, but now I can't even get the device to connect to PC or boot up. Every time I connect the USB, only a dimmed Garmin logo showed up for 2 sec, then the screen went to black, which really sucks. I don't know what else I can do at this stage. It won't boot when I long-press the power button, so I can't even try the preboot trick (it feels super hard to do anyway).
I'm not one to be pessimistic however this isn't looking good for recovery now. However, generally speaking if a device shows the logo splash screen it can still attain preboot. Modern devices can be notoriously hard to get into prebood and then will only maintain it for a very brief period, mere seconds, if you don't miss that brief chance to start the flash the data stream from Updater.exe holds it in preboot until the flash finishes. So if a flash isn't initiated almost immediately the device will drop preboot. Garmin seems to have intentionally done that to discourage users doing flashing via Updater.exe which to me seems almost mean-spirited of them. You can try this method:
  • Ensure the device is fully OFF.
  • Plug a suitable USB cable directly into a USB2 port (Not a USB3 port and don't use a hub). Make sure to use a REAR USB2 port only, front ports may not work so reliably for this.
  • Load the Cure firmware to Updater.exe and select the radio button next to "USB Device". Leave the GUI visible on your computer with your mouse cursor positioned over "OK" button.
  • Hold the upper LH corner of the device screen (use your left thumb is best) and while watching the window next to 'USB Device' quickly plug the cable into the device.
  • IMMEDIATELY you see the device details appear in the window either click "OK" on Updater's GUI or just hit your computer's Enter key.
  • Keep firmly holding the screen until 'Loader' or 'Software Loading' appears on it at least, if unsure hold until the flash is reported as successful.
  • If you miss it start again ensuring the device is fully OFF.


The device will stall on the logo screen and stop turning off when cure fw is loaded and you should again have access to the file system in Mass Storage Mode. Remove files or just reformat again, etc..

BTW, is there anyway to completely drain the battery without opening the case? I found it need torx-5 screwdriver which I don't have.
Leaving it off for an extremely long period of time will eventually totally exhaust the battery, but we're talking many months or a year or so for a fully charged reliable battery.