What is iPhone DFU mode
DFU stands for Device Firmware Update. DFU mode is a state that you can put your iPhone into where it can interface with iTunes but does not load the iPhone operating system or boot loader. This sets the DFU mode apart from the recovery mode.
What is DFU mode used for
It is pretty easy to understand what is DFU mode used for. Since you’re looking for information on DFU mode – it is evident that you want to change the firmware on the device. Firmware change is needed to jailbreak a device or device unlock or SIM unlock.
How to Enter iPhone DFU mode
- Connect the iPhone to your computer and launch iTunes.
- Turn the iPhone off by holding down the power button and using the slider to confirm turn off.
- Hold down the sleep/power button and home button together for exactly 10 seconds, then release the power button.
- Continue to hold down the Home button for further 10 seconds until the screen becomes completely blank.
DFU mode leaves your phone completely turned off. A pitch black iPhone screen signifies a DFU mode. If you see the Apple logo or the “connect to iTunes” screen on your iPhone, you’re not in DFU mode. DFU leaves the screen of the iPhone completely black turned off.
DFU mode is different than recover mode, wherein iTunes restores your iPhone to its original factory settings with the latest iOS and firmware. DFU mode allows you to choose and change the firmware of your iPhone.
How to Exit DFU Mode
To exit DFU mode, simply hold down the sleep / power button and the home button together until your iPhone disappears from the device list in iTunes, then turn on the iPhone as normal.