Iphone 5 stuck in DFU endless loop

MrMagoo

Hi All,

Any help here appreciated before I throw the phone out the window!

I was successful in bringing an old iphone 5 back to life for my mother to use and it was working fine until yesterday when it simply died. It then started to reboot, flashes the Apple logo for about 3 seconds, then black (off), and repeat endlessly.

I followed some instructions online to enter DFU mode (wake & home buttons) and iTunes on PC recognized the phone, suggested it needed to be restored, downloads iOS 10.3.3 and attempts to install it to the phone. Then, the phone reboots, goes straight into DFU mode again and iTunes reports error 21 (unknown error) and cannot continue.

Some other info:
*It will only switch on when plugged in to a power supply or PC; nothing without it.
*The phone is a few years old and battery was draining very quickly before I gave it away so had a new one put in with the local phone-fixer shop and it all worked much better. That was only about 8 weeks ago.
*Even when plugged in to the wall now, it just sits in DFU mode asking to be connected to iTunes, but the same error 21 happens over and over again when I try to restore.

Any suggestions? I honestly never thought my OAP mother would be an IPhoner but she absolutely loves this thing and I'd like to get it back working. Not enough cash for a new one just yet so that's where the good people of Boards come in

Thank you!

brophs

MrMagoo wrote: »

Hi All,

Any help here appreciated before I throw the phone out the window!

I was successful in bringing an old iphone 5 back to life for my mother to use and it was working fine until yesterday when it simply died. It then started to reboot, flashes the Apple logo for about 3 seconds, then black (off), and repeat endlessly.

I followed some instructions online to enter DFU mode (wake & home buttons) and iTunes on PC recognized the phone, suggested it needed to be restored, downloads iOS 10.3.3 and attempts to install it to the phone. Then, the phone reboots, goes straight into DFU mode again and iTunes reports error 21 (unknown error) and cannot continue.

Some other info:
*It will only switch on when plugged in to a power supply or PC; nothing without it.
*The phone is a few years old and battery was draining very quickly before I gave it away so had a new one put in with the local phone-fixer shop and it all worked much better. That was only about 8 weeks ago.
*Even when plugged in to the wall now, it just sits in DFU mode asking to be connected to iTunes, but the same error 21 happens over and over again when I try to restore.

Any suggestions? I honestly never thought my OAP mother would be an IPhoner but she absolutely loves this thing and I'd like to get it back working. Not enough cash for a new one just yet so that's where the good people of Boards come in

Thank you!

I had a similar thing happen to me a few years back. From memory, it was down to the battery being completely shot. I bought a new battery on Amazon for less than a tenner, fit it myself and the phone worked fine. I’m not an expert, but I think it’s likely that the new battery is an issue. Perhaps the shop would check it and replace if necessary?

MrMagoo

Cheers. I did think it was a power thing, so I think I'll bring it back to the guy who changed the battery and have a chat with him.