If your iPhone 5 was manufactured through March 2013, then there’s a possibly that the power (sleep, wake) button has or will stop working or will work intermittently. Apple has recognized that its their fault for this problem to be happening and will replace the power button for free on affected devices. Apple’s iPhone 5 Sleep/Wake Button Replacement Program is available on the US and Canada as of today and will be available in other countries starting May 2. You’ll need to send your device to Apple or take your device to an Apple store for a free replacement. To check if your iPhone 5 is eligible for a free power button replacement go to Apple’s iPhone 5 support website and type the iPhone serial number in the box.