DFU stands for Device Firmware Update, and it’s the deepest type of restore you can do on an iPhone. An Apple lead genius taught me how to put iPhones into DFU mode, and I’ve done it hundreds of times. Surprisingly, I’ve never seen another article explain how to enter DFU mode the way I was trained. Some of the information out there is just plain wrong. In this article, I’ll explain what DFU mode is, how firmware works on your iPhone, and show you step-by-step how to DFU restore your iPhone.
What You Need To Know Before We Begin
- The Home Button is the circular button below your iPhone’s display.
- The Sleep / Wake Button is Apple’s name for the power button.
- You’ll need a timer to count to 8 seconds (or you can do it in your head).
- If you can, back up your iPhone to iCloud or iTunes.
How To Put An iPhone In DFU Mode
- Plug your iPhone into your computer and open iTunes. It doesn’t matter if your iPhone is on or off.
- Press and hold the Sleep / Wake Button and Home Button together for 8 seconds.
- After 8 seconds, release the Sleep / Wake Button but continue to hold the Home Button until iTunes says “iTunes has detected an iPhone in recovery mode.”
- Let go of the Home Button. Your iPhone’s display will be completely black if you’ve successfully entered DFU mode. If it’s not, try again from the beginning.
- Restore your iPhone using iTunes.
A Word Of Warning
When you DFU restore your iPhone, your computer erases and reloads every bit of code that controls the software and hardware on your iPhone. There’s the potential for something to go wrong.
If your iPhone is damaged in any way, and especially if it’s water-damaged, a DFU restore may break your iPhone. I’ve worked with customers who tried to restore their iPhones to fix a minor problem, but water had damaged another component that prevented the restore from completing. A useable iPhone with minor problems can become completely unusable if a DFU restore fails because of water-damage.
What’s Firmware? What Does It Do?
Firmware is the programming that controls the hardware of your device. Software changes all the time (you install apps and download new email), hardware never changes (hopefully, you don’t open your iPhone and rearrange its components), and firmware almost never changes – unless it has to.
What Other Electronic Devices Have Firmware?
All of them! Think about it: Your washing machine, dryer, TV remote, and microwave all use firmware to control buttons, timers, and other basic functions. You can’t change what the Popcorn setting does on your microwave, so it’s not software – it’s firmware.
DFU Restores: All Day, Every Day.
Apple employees restore a lot of iPhones. Given the option, I’d always choose a DFU restore over a regular or recovery mode restore. This isn’t official Apple policy and some techs would say it’s overkill, but if an iPhone has a problem that can be resolved with a restore, a DFU restore stands the best chance of fixing it.
Thanks for reading and I hope this article clarifies some of the misinformation on the internet about how to enter DFU mode and why you’d want to use it. I encourage you to embrace your inner geekiness. You should be proud! Now you can tell your friends (and kids), “Yeah, I know how to DFU restore my iPhone.”
Thanks for reading and all the best,