IPhone 5 no signal? And keeps searching?

I have a iPhone 5 and it has no signal and comes up with searching every now and then and still has no signal was just wondering what is it? And if my apple warranty will cover it? And will the give me a new phone or fit it?

Try a couple things. Take the SIM card out and put it back in. Then go to Settings-General-Reset-Reset Network Settings. If it is still acting up contact your carrier. Make sure they simply do not get you on over to Apple because Apple will make you do what I just said.

If that doesn't work it may be your SIM card and you should go to a carrier store to get it replaced. If all else fails backup and restore it through iTunes. If it still doesn't work then it's the phone and so long as it's in warranty Apple will service it.

I should add that they will know if you tried the above steps. They will do it themselves including the extreme DFU mode to get it working which wipes the phone clean. If it works they will simply send the phone back with a bill.