wifi greyed out after update to ios7

After upgrading from a 100% functional iphone 4s from ios 6 to ios 7.

wifi stopped working. after reboot, wifi setting is greyed out. bluetooth button is shown as busy circle...

done: network reset, backup restore, dfu mode with fresh ios7 file....

turning wlan on in new config bar is available, but does not turn on wifi....

apple diagnostic tool said that I have a charging problem, but everything is fine with charging batteries.

I can not believe that there a so many coincidences with hardwareproblems?