iPhone that doesn't turn on might be hardware-damaged in some way. It can be either a dead battery, dysfunctional charging port or something worse. Lets make some test before we jump to hardware malfunction conclusions.
Solution #1
Before you do anything, let's just make sure that it's really a hardware problem and not software - connect the iPhone to computer using a working cable, then check to see if iTunes recognizes it. If now, it is maybe in a DFU mode: Hold down the "Home" + "Power" buttons simultaneously. After 12 seconds, release the home button and continue to hold the power button until the screen lights up and the Apple logo comes on.
Solution #2
Hold the home button and power button till the silver apple appears then see if that works if not then do the following :
- turn off your iPhone
- connect it to your laptop
- hold the power button for 3 seconds
- keep holding the power button , but aswell as the power button hold the home button aswell for 15 seconds
- release the power button and keep holding the home button until you hear your itunes make a sound
Solution #3
Hold down the power button and the home button, until it goes black. Then restart it. It should work, and it might stay at the apple logo.
Solution #4
- Plug your iPhone into a computer or laptop
- put your iphone into recovery mode (Turn off completely while NOT connected to the Mac)
- exit itunes, hold down the home button while plugging in your phone into iTunes and it should read "iTunes has detected a phone in recovery mode")
- once you're in recovery mode you can go to your Mac HD » Applications » Utilities » System Profiler.
- You should see your iPhone via USB connection. Click on it and it should have all the info there (you can use Command+Shift+4 to take an onscreen shot and save all the info as a picture file)
Solution #5
Hold down the home button and the power button for ten seconds. Then release the power button while still holding the home button and then connect to your computer. Keep holding the home button until your computer gives you the restore option.
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