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iPhone overheating and burning through the battery fast? This weird fix might help

Frustrated by your iPhone's bad battery life and constant overheating? Tearing out your hair because you think you've tried everything? Try this!
Written by Adrian Kingsley-Hughes, Senior Contributing Editor
Jason Cipriani/ZDNET

Battery woes continue to plague some iPhone users, and the latest iOS 16.5.1 release didn't bring any relief. While for many, the issues will sort themselves out, for some the problems persist and none of the tips or tricks have any effect.

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I was trawling through the Apple Support Forums the other day looking for a solution to an unrelated problem when I came across a possible solution to the iPhone's severe battery drain issue.

That solution? Reload iOS onto the iPhone, and then recover your data from a backup. Yeah, I know, it sounds like a lot, but if it works -- and a few people responded in the thread to say it did for them -- then it's worth doing.

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And if it doesn't work, you've not lost anything (except for a bit of time).

But, since you are deleting everything on your iPhone in order to be able to do this, it's important that you have a working backup, otherwise you're going to find yourself in a world of pain.

How to implement this solution 

1. Create a backup… or two!

There are two ways to back up an iPhone -- to the cloud using iCloud backup, or to a Mac or PC using iTunes. Both methods are detailed on Apple's support site.

I recommend that you have both a backup in the cloud and a local backup, just in case anything goes wrong.

Apple's support document doesn't mention that if you want your passwords backed up when making a local backup with iTunes, you must encrypt your backup data and protect it with a password by selecting "Encrypt local backup."

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That one catches a lot of people out. Also, don't forget this password!

Once you've saved your backup, don't use your iPhone, because before you know it, you'll have new data that you don't want to lose and you'll need to create new backups.

Another thing I like to do before deliberately wiping an iPhone is to make sure I know my iCloud password, especially if I expect to restore my iPhone from the cloud.

2. Enter the DFU mode

iPhone in DFU mode connected to a computer

DFU stands for Device Firmware Update and is a mode that is normally used to allow iOS to be loaded onto an unresponsive iPhone. Here we're going to use it to force a clean installation of iOS.

To do this you will need access to a Mac or PC running iTunes. You can't do this from the iPhone directly.

To put your iPhone in DFU mode, you'll need to perform some button presses that feel like sleight-of-hand tricks, and these will leave you feeling like you need an extra hand or two.

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Follow the instructions carefully and take your time. It can be fiddly, and it might take you a few attempts to get your iPhone into DFU mode and recognized by the Mac or PC.

Once the iPhone is in DFU mode and connected to the Mac or PC, choose Update from the popup and follow the prompts.

If, while downloading the update, the iPhone exits the recovery mode screen, don't panic! This can happen after 15 minutes of inactivity. Allow the download complete on the computer and then put the iPhone back into DFU mode and reconnect it. 

3. Get your data back.

Once you've finished installed iOS in DFU mode, it's time to recover your data from the backup you made earlier.

How you do this depends on which backup method you used. Both methods are pretty straightforward.

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If you did both, then you have a choice as to which to use to restore your iPhone. 

Unless you have a fast internet connection, I'd probably use the local backup made using iTunes. Remember that password you used to encrypt your backup? Well, I hope so, because you'll need that now.

4. Test the iPhone

Use it normally for a week or so and see what the battery life is like. 

Note that it might take a couple of days for things to settle down after reinstalling iOS because there's a lot of background housekeeping tasks that need to be done following the installation of iOS and restoration of your data.

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