How to fix Broken or greyed out wifi

Try the suggestions here to see if they resolve your problem:

http://support.apple.com/kb/ts1559

If these don't work you may have a hardware problem. Visit an Apple store for an evaluation or contact Apple Support.

Indeed, the WiFI radio chip is known to overheat on the iPhone 4S under iOS 7. Chances are you have to render a visit to the Apple Store in the very near future.

Hi guys, I had the same issue of wifi. And you guys helped a lot. I tried every technique for almost 3 days. I reset the network settings, reset phone settings and reset phone settings with erasing all the data/media. It didn't work. I put my phone in freezer twice for almost 20 minutes. It worked for 10 minutes and again got greyed out and searching. I was completely exhausted and fed-up. Finally today I went to a phone repair shop, told him about the issue, and he was like "No problem, your phone will be okay after 20 mins" as if he already knew, and he did. Because later I spoke to him and he said this is a hardware problem by Apple itself when iPhone 4S products were manufactured in China. Well, he took a reasonable price for repair. And now my iPhone's wifi is working fine. He changed the chip. So, say NO to all these techniques and go for a repair.

Seriously, I was an Apple lover from their first product. And I have been using Apple products since then. But sorry Apple, you lacked. Very bad experience for the first time. If it was an issue with few peeps, but all over the globe 150k people are facing the same problem. Good bye apple. Switching to Android. I hope next time when Apple would want to manufacture their products, they should certainly keep in mind each and everything, hope so but still unhappy with Apple. Exhausted user here. I will never use an iPhone now.