How to Put iPhone in DFU Mode
DFU mode stands for Device Firmware Mode which is the pre-IOS boot state in the iPhone commonly referred to as iBoot. You will have to put iPhone in DFU mode incase you wish to upgrade or downgrade its firmware.
Since iPhone upgrades and downgrades involve modifying the IOS as a measure to install third party apps and preserve baseband firmware, knowing how iPhone DFU mode works is very important.
Difference between DFU and Recovery Mode
In order to understand DFU Mode better, it probably is important to understand how Recovery mode differs from it.
DFU and recovery modes are two different boot states in iDevices and they all precede loading/booting of the iPod or the iPhone.
DFU mode is present in the iPod or iPhone when it has been turned off, but can still communicate with iTunes. This is also the state when the ROM iBoot and operating system in the iDevice have not yet loaded.
Recovery mode, on the other hand, is the state in the iPhone when software like ROM, has loaded.
An example of IPhone in recovery mode is when it goes through a continuous restart loop, or when it shows the iTunes logo just before it loads the Home screen.
From the above explanation, it is safe to assume that iBoot mode sits between DFU mode and Recovery mode.
What is iBoot?
iPhone iBoot (boot loader) is a nifty little bootrom software embedded in the iPhone that first boots, and then allows the general IOS to boot off the iDevice hardware. It is a little like the ROM BIOS which starts up, checks and assesses all hardware components in the personal computer before handing over authority to the main operating system.
The two modes states mentioned above are popular because they are very important pre-IOS installation states.
If ever you are to change your iPhone Operating System (IOS) by upgrading, ‘repairing’, or downgrading it, you will definitely have to choose the appropriate of the two states.
For example, ‘repairing’ or upgrading the normal IOS from Apple will necessitate that you have your iDevice in Recovery mode. The assumption here is that you care less about upgrading your iDevice baseband.
If however you intend to downgrade your iDevice to an earlier IOS version, you definitely will have to go the DFU mode.
DFU state is where no boot software (iBoot bootloader) and identity baseband have been loaded. This is a state in the iDevice when it is at its bare minimum. An iDevice in DFU mode has a black screen and the state cannot be reversed even by connecting it to the computer.
AS mentioned above, an iDevice in Recovery mode has already gone beyond the initial boot process (iBoot bootloader) and, therefore, hard to manipulate.
How to Enter iPhone DFU Mode
In order to bypass all the iBoot restrictions and install any type of IOS IPSW, it is best to put your iPod or iPhone in DFU mode.
Entering DFU mode in an iPhone or iPod can be done using iTunes, Redsnow, iREB e.t.c.
To enter iPhone DFU mode, follow these instructions:
- To start off, make sure your iDevice is connected to the computer.
- Press and hold the power/sleep button for about five seconds till it shows Slide to power off.
- Go ahead and slide to power it off.
- Then press and hold on to the POWER button for three seconds. Around now, especially if your iDevice is connected to the computer, the Apple logo should appear on the screen.
- While still holding on to the POWER button, press and hold on to the HOME button for ten more seconds.
At about the seventh of the ten seconds, the Apple logo should go off.
- At ten seconds, release the POWER button and continue holding on to the HOME button for ten to fifteen more seconds.
- After this, your iPod or iPhone should be in DFU mode, and to prove this connect it to your computer and see the response. Normally an iDevice in DFU mode should not boot up. If it does, you probably did not accomplish the process very well.
- You can start over and try to do it well this time around. Different people have done this a number of times before getting it right. So, do not be afraid to fail and do not worry about damaging your iDevice. It should withstand all the hiccup.
- Select Pwned DFU mode in the next window.
- Click Next in the next window and follow the instructions.
- They are the same instructions as explained above, only now you are guided through some kind of a timer.
- If you are jailbreaking using iREB, download and start iREB.
- Follow the instructions provided. iReb seems to get it right all the time.
Have you struggled to enter iPhone DFU mode?
Why do you think so?
Video Showing How to Put iPhone in DFU Mode
How to Put iPhone Out of DFU Mode
Of course, you may have been fiddling around with your iPod or iPhone and got your device stuck in DFU mode. Don’t worry. The return journey to normalcy is very simple.
In order to get out of DFU mode, simply press and hold POWER + HOME button for approximately fifteen seconds.
The Apple logo should appear on your iPhone screen and your iDevice should now boot up normally.