If Flipper Zero's firmware is corrupted, the device can be restored using the built-in DFU boot loader. This bootloader can't be changed when updating the firmware, so the recovery method is suitable for such cases:
- If the firmware is corrupted and the normal update method does not work.
- If there is no image on the screen, the device does not respond to button presses and a normal reboot does not work.
The device may not work if the battery is low. Connect the device to the USB and try to charge the battery before attempting to restore the firmware.
To activate the built-in bootloader:
- Unplug Flipper Zero from the USB. If you do not disconnect the device from the power supply, the DFU mode will not activate.
- Press and hold the :ok:OK + :back:BACK buttons for 30 seconds. Then release them. If the firmware is corrupted there will be no indication on the screen, this is normal.
- Connect the device to the computer. Flipper Zero should be detected as a DFU in FS Mode.
When connected to a computer in recovery mode, there will be no indication on the Flipper Zero screen. If the device successfully enters recovery mode, it will appear in the Device Manager as DFU in FS Mode.
Check the connection in Windows:
- Open the Device Manager.
- Find the device DFU in FS Mode .
By default there is no driver for the Flipper Zero DFU device in Windows, it is installed automatically when you install the qFlipper application.
The qFlipper utility automatically performs firmware recovery if it detects Flipper Zero connected in DFU mode.
To restore the firmware:
- Run the qFlipper.
- Connect Flipper Zero in DFU mode. The program will automatically detect the device in recovery mode. The firmware update button will be blue.
- Press the Repair button. The program will perform a full installation of the firmware and databases. All saved settings in the Flash memory will be cleared. The user data on the microSD card will be saved.