Postagem original de: Rany ,
By any chance, did this occur after an iOS updaate? If it did or even not, try to restore a completely new software. 1/ Prepare: - back-up your phone's content to iCloud or the latest version of iTunes on your computer, - turn off Find My iPhone. 2/ DFU mode: - press power button for 3 seconds, - start pressing home button without releasing power button, 12 seconds, - at 12 seconds, release power button. Keep pressing home button for another 15 seconds. - at this point your screen should be black. If you see "connect to iTunes" you're in Restore Mode not DFU Mode. Either repeat or try your luck with that mode. 3/ Restore: - start the latest iTunes on your computer, - use an original cable to connect your iPhone to your computer, - you should get a prompt from iTunes saying it detected an iPhone in restore mode, - you will be also prompted to download and restore the latest version of iOS, - accept and leave your iPhone connected and undisturbed until it finishes the process. If your Internet connection is slow, it can be a while. The new software is ~1.6GB. - test your phone. If ok, restore your back-up and turn on Find My iPhone. If the above does not help, come back here to seek help identifying what hardware issue may be causin this. For this, do you have access to another known good iPhone 5?