My new phone keeps turning itself on and off
iPhone 5
Do you mean the backlight keeps turning on and off? Go to Settings>General>Auto-lock and select "never" if you never want the screen to turn off on its own.
Try a Reset...
Reset ( No Data will be Lost )
Press and hold the Sleep/Wake button and the Home button at the same time for at least ten seconds, until the Apple logo appears. Release the Buttons.
http://support.apple.com/kb/ht1430
If no joy...
Connect to iTunes on the computer you usually Sync with and “ Restore “...
my new iphone 5 keeps turning on and off by itself
