DFU Mode Restore (iOS)
DFU mode restores on iOS devices should only be necessary if a traditional restore fails.
and for the people in the back...
DFU mode restores on iOS devices should only be necessary if a traditional restore fails.
In terms of troubleshooting software issues on an iOS device, it is always advisable to progress from least invasive steps first:
Level 1 (least invasive): Normal device operation software update via iTunes. Just plug the phone into a computer with an updated version of iTunes.
Level 2: Recovery mode (device rebooted into connect to iTunes screen) iTunes update. If successfully there will be no data loss and device will be updated to latest Apple signed iOS version compatible with iOS device.
Level 3: Recovery mode restore. This WILL erase everything on device and update device to latest signed iOS version
Level 4 (most invasive): Device Firmware Update (DFU) resotore (device rebooted and and powered on to a blank black screen. When in DFU mode, the only available iTunes option will be to restore device. If device receives itunes error message with KGB (known good) cable, then hardware issues are suspected. If data is not important, this should be done before opening a device.
How to enter device into recovery mode:
iPhones 6s(+) and older:
- Connect device to iTunes or 3utools computer via lightning cable
- Press the side/power button and home button simultaneously.
- Once the screen has turned black continue to press both button until the connect to iTunes logo has appeared.
iPhone 7(+):
- Connect device to iTunes or 3utools computer via lightning cable
- Force restart device by simultaneously pressing the side/ power button and volume down.
- After device has rebooted continue to press both button until the connect to iTunes logo has appeared.
iPhone 8(+) and newer:
- Connect device to iTunes or 3utools computer via lightning cable
- Force restart by rapidly tapping volume up, then volume down, then press and hold side/ power button until device restarts.
- After device has rebooted continue to press side/power button until the connect to iTunes logo has appeared.
How to enter device into DFU recovery mode:
iPhones 6s(+) and older:
- Connect device to iTunes or 3utools computer via lightning cable
- Press the side/power button and home button until the screen goes black
- Once the screen goes black continue to press both button for a count of approximately 7 seconds
- release side/power button while still pressing the home button.
- Keep pressing the home button until iTunes or 3utools recognizes the device in DFU mode.
- If done correctly, device will be powered up to a blank black screen and will appear in iTunes. If unsuccessful, force restart and try again...
iPhone 7(+):
- Connect device to iTunes or 3utools computer via lightning cable
- Press the side/power button and volume down simultaneously
- Once the screen has turned black, continue to press both button volume down and side/power buttons for approximately 7 seconds
- Release side/power button while still pressing volume down button
- If done correctly, the device will continue to have a black screen & will appear in iTunes or 3utools with only the option of a full restore
- If unsuccessful, hold side/power button & volume down to force restart and try again
iPhone 8(+) and newer:
- Connect device to iTunes or 3utools computer via lightning cable
- press & release volume up, followed by volume down
- then press and hold side/power button until the device screen goes black (approx 13 seconds)
- Once the screen goes black continue to press both button volume down and side/power buttons for approximately 7 seconds
- release side/power button while still pressing the volume down button.
- Keep pressing the volume down button until iTunes or 3utools recognizes the device in DFU mode.
- If done correctly, device will be powered up to a blank black screen and will appear in iTunes or 3utools. If unsuccessful, force restart and try again...
*note: the timing for iPhone 8 and higher is far more precise and it is quite difficult to achieve on first try. You can put an iPhone 8 and newer into DFU mode, you just have to try harder.