If an Apple device no longer responds (properly) or you want to exit the recovery or DFU mode described above, you can perform a hard reset. Apple provides detailed instructions for this, as there are different key combinations that must be pressed for each model and iOS version. This is essentially a forced restart of the device.
Recovery
There is a “soft” recovery mode, which is also clearly documented by Apple. You should first try to revive the device using this mode. If a system recovery fails in this mode as well, the next step is DFU mode:
DFU
DFU (Device Firmware Update) mode is designed to get a device that has been damaged by software back up and running. It is essentially the lowest level of firmware, an emergency rescue mode.
First of all, it should be noted that this mode cannot be used to bypass an iCloud or activation lock, and even in this special mode, the device can only be restored to iOS or iPadOS signed by Apple. So it really only helps to completely reset the local device; online services (such as iCloud) are not affected.
iFixit has instructions available, but Apple does not even document this special mode, as it is only intended for internal use.
Requirements:
- Computer with the latest version of iTunes
- Suitable USB cable for the device
- Apple device switched on
Then let’s get started:
- Connect the device to the computer via USB cable.
- Turn off the Apple device.
- Open iTunes.
- Start DFU mode according to the iFixit instructions.
- A message saying “…needs to be restored…” should appear in iTunes.
- Click “Restore” and iTunes will download the appropriate iOS or iPadOS version and restore the device.
- If you hold down the Shift key and click “Restore” instead, you can specify a firmware file yourself, but it must still be signed.
If none of this helps, you’ll probably need to contact Apple or a service provider.
Good luck!