Fourth generation iPhone. Repair is straightforward, but the front glass and LCD must be replaced as a unit. GSM / 8, 16, or 32 GB capacity / Model A1332 / Black and White.

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Why can't my iPhone 4s restore?

Recently I have replaced my Iphone 4s screen and everything worked perfectly fine right after I had assembled it. After about 2 hours, my iphone 4s turned off twice. The first time, I started it back up and it worked. The second time, I was hopeless and the screen would not start back up. Later, I tried to connect it to Itunes and it can't restore because of error 21. I've tried literally everything (redsnow extras, modify hosts file, ipsw file, replacing battery, and DFU mode). Can someone help me resolve this problem?

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Error 21 is a battery issue if the phone is rebooting or switching off by itself it's battery.

Had error 21 on a few iPhones that customers brought in and a new battery fixed it..

All you need is a battery and jack is already geting you to replace the motherboard lmao

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Have you tried another computer? See if it works on that. If using DFU on another computer doesn't work, then your logic board will need to be replaced.

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if you replaced the screen and the device went off, then it could be the screen which sucks to much energy and that could damage your iphone.

plug the screen off and restore with that opened iphone.

if that doesnt help, i hope you will only need a new battery.

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Anh Nguyen will be eternally grateful.
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