Quote Originally Posted by Qdshayes View Post
............ If I press and hold the power button continuously, I get the screen calibration screen come up, but then it eventually goes into the map loading sequence and then fails. (All this is of course while pressing in the bottom left corner of the screen)
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Background facts and preparation:
  • The unit is in pre-boot during the period before the white calibration screen is shown.
  • If a flash is not initiated in that period it exits pre-boot to the calibration mode.
  • The pre-boot period varies depending on the model, for some Garmin units it's as short as 10 seconds and always exits if a timely flash is not initiated.
  • [Only registered and activated users can see links. ] must be loaded on the PC for the unit to be accessed by Updater.exe in pre-boot mode, if not sure just load again.


Step by Step Instructions:
Please take a deep breath and go slow. The only time you need be quick is for Points 7 & 8, otherwise take your time but follow this precisely:
  1. Drag the cure3 rgn file onto Updater.exe
  2. Leave Updater's GUI visible on the PC Desktop with the Radio Button enabled for 'USB Device'
  3. Position the mouse cursor over 'OK' on the GUI
  4. Connect the USB cable directly to a rear port of the PC [don't use a hub or front port]
  5. Ensure zumo is fully off
  6. Press and hold the lower left corner of the zumo's screen then press and hold the power button
  7. Quickly connect the USB cable to the zumo [release power button when zumo turns on] while watching the window next to 'USB Device' on Updater's GUI
  8. Immediately you see the zumo's details appear in the window click 'OK' or press Enter key on the PC keyboard
  9. Don't release the screen at least until you see 'Loader' or 'Software Loading' or similar message on the zumo screen [or just hold it for the entire flashing process if you want]

The unit should then be shown in Mass Storage Mode, so make a backup of the file system now. After, delete the guilty file/s if you know what caused it to brick. If you don't know then use RMPrepUSB to reformat it and after formatting create a folder named Garmin in the root. Safely disconnect from PC. Again enter pre-boot and flash the original firmware which should allow it to boot normally. Read again the initial post in this thread very carefully.