Why iPad/iPhone battery drains even when powered off?

Question

When I power an iPad off (latest available device and software) while its battery is at 100% charge, after a week or so of it sitting in a drawer, its battery is completely drained of power and it can no longer boot up without recharging. If I do the same with my nintendo gameboy advance, the device still boots up and has almost full charge even after a year of sitting in a drawer, powered off. Why is this happening? What am I missing?

Crosseye_Jack · Accepted Answer

Hard to say without having the device in hand and you willing to allow some probative research (and from my screen replacement days, people tend to get twitchy off you have to remove the person from the phone for longer than an hour, heck I was the same when I last had apple replace my battery).
It could be a number of things, a bad battery not retaining charge as well as it should. It could be that one of the other processors on the device didn’t get the message to power off (which is my guess).
If it’s a continuing issues I suggest backing up the device, factory resetting it and then reflashing iOS (you can use ipsw.me or 3utools to download the ISPs file needed, if you used 3utools, you can then use that to flash it or (iirc) hold down shift/option as you click the restore button in iTunes (with the phone connected) and then select the ipsw file downloaded.
Restore the phone with your fresh backup and try again. Hopefully that will kick anything that was hanging around after power down to get the message.

ssss11 · Answer

There&rsquo;s a chip that is on even when the device is off - others will have more information and links. There was discussion recently about this.I think it&rsquo;s to keep Bluetooth on for &lsquo;FindMy&rsquo; functionality&hellip;

neximo64 · Answer

It's not actually off when you turn it off.

bellyfullofbac · Answer

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