iPhone 5 proximity sensor not working

[IAmAuthority]

Hmm yeah I don't think it's suppose to change anything on home screen.

 

[WreakingHavoc]

It would be kind of nice if the screen locked when it was covered though, just like the magnetic one on BlackBerry.

 

[site32]

I don't quite understand you, my reading is normal situation is, call status, the receiver to ear or other object, the screen will be black, as long as a left, the screen will be bright.
If the screen is not automatic light, that may be light sensor element is broken, this kind of circumstance, the screen will not automatically bright, need to repair.

 

[IAmAuthority]

Thankfully if you need a new screen you'll be able to get one at no cost so long as the device is faulty. Go ahead and contact whoever you purchased the phone through, they should be able to help you.