I work at a third party Apple repairer. We get 1-5 calls a day about the greyed out WiFi issue. 99% of the time, it's a 4S and we have to refer them to Apple fo

I work at a third party Apple repairer. We get 1-5 calls a day about the greyed out WiFi issue. 99% of the time, it's a 4S and we have to refer them to Apple for repair. It can usually be fixed by resoldering the WiFi chip but we can't guarantee the repair, so we don't offer it. Not an iOS 7 problem either, but a common thing is for it to happen after an OS update.