This seems silly, I know, but if you iPhone won't turn on, the first thing you should do is check to make sure that it's not off. To do this, just hold down the Hold button at the top right corner on the edge of the phone for a few seconds. If the phone is off, it should turn on. If it's on, you may get the slider that lets you turn it off.
If it was off, let it boot up. If it was on, restarting it by turning it off and then turning it back on is probably a good idea.
If your iPhone wasn't turned off or won't restart, try this instead: hold down the Hold button and the Home button on the bottom center of the front of the iPhone at the same time. Hold them both for at least 10 seconds (there's nothing wrong with holding for 20 or 30 seconds, either, though if nothing has happened at that point, it probably won't). In many cases, the silver Apple logo will appear and the phone will boot up.
Again, this may seem obvious, but it's actually pretty common. If your iPhone's battery runs very far down, the iPhone won't turn on. That's because it's using its remaining battery life to preserve your data and settings.
So, your iPhone could be refusing to turn on because its battery doesn't have enough juice. In that case, plug your iPhone into a wall charger or into your computer (plug it directly into the computer; some USB ports on keyboards don't have enough power to charge iPhones). Let it sit for 10-20 minutes. If it was low on battery and needed a charge, when it's got enough juice to power the screen, it will turn on and show you its charging status, starting with the red battery icon.
If you suspect your phone ran out of battery but this technique doesn't work, it's possible that your charger or cable is faulty. Try using another charger or cable and see if things change.
During this process, you may also want to make sure there's no lint packed into your cable or the iPhone's dock connector. This isn't a hugely common problem, but a lot of pocket lint could interfere with the iPhone getting a charge.
If those options don't work, sometimes your best bet is to restore your iPhone to its factory settings. This erases all the data and settings on your phone (hopefully you synced it recently and backed up your data), but it can solve a lot of problems. Normally, you can just sync your iPhone and click the Restore button in iTunes, but if it won't turn on, you need a different technique:
- Plug the iPhone's USB cable into the dock connector, but not into your computer
- Hold down the iPhone's Home button
- Now plug the other end of the USB cable into your computer
- This will open iTunes, put the iPhone into recovery mode, and let you completely restore the iPhone.
In some rare circumstances, the issue might not be so much that your iPhone won't turn on as that it won't boot up properly. This often takes the form of the phone trying to start, getting to the silver Apple logo, and then restarting itself. This is most common after jailbreaking or when trying to install an iOS update without enough battery life.If you're facing this problem, try putting your phone into DFU mode and resetting it.Another rare circumstance that can cause a problem with some iPhones is a malfunction in the proximity sensor that turns the iPhone's screen on and off when you hold it up to your face to make a call. This malfunction can cause the screen to be turned off even when the phone is on and not near your face.If you're facing this issue, it can usually be solved through software, rather than repairing or replacing the phone. In this case, hold down the Home and Hold buttons as outlined above to restart the phone. When it restarts, the screen should be working. If it is do the following:- Tap the Settings app
- Tap General
- Tap Reset
- Tap Reset All Settings. This erases all your preferences and settings on the iPhone, but won't delete your data.
- Confirm the reset. This should resolve the proximity sensor problem.
THIS IS BY :