If this is the case, then the necessary permanent solution is to reflow the Murata SW SS1830010 Wi-Fi chip on the logic board. And don’t expect any other solutions will work out .Try to change this chip via any local iphone service centers .The better option will be replacing yours with a Dead iphone 4s wifi Chip.
How to fix iPhone 4s Wifi Grayed Out ?
-Want to fix it via Heating or Cooling method (Temporary)?
(For me it worked for 30mnts)
* Heat it till this warning msg arrives using a hair Dryer (2mnts) & Cool it in freezer for 5mnts after putting it in a plastic Bag.(Try with your own risk 🙂 )
-FixIT Gives a Reply in this way :
Want to Change the chip your self ?
Whats Behind the Heating Technic ??
Drastically changing temperature on electronic components causes solder joints and other connections/components like capacitors, to expand and/or contract. It is usually used as a quick way to diagnose where a problem is.
So in the 4S’s case, it may be bad solder joints, a bad capacitor or even the wifi chip (USI 339S0154)’s oscillator isn’t calibrated correctly and the change in temperature allows it to change slightly. However I haven’t looked at the datasheet to verify this.
#I Recommend you to replace the WIFI Module with a Dead Iphone ##only with the help of an expert .:) Which charged me 800 rupees in Calicut,Kerala – INDIA