Date : 18/04/2013

i found out that WiFi button on my iPhone is greyed out as obvious i become quite worried about it
and i was totally messed up what i have to do about it and i how can i fix it . so i went to some test on my iPhone. and i got lucky at one of them here i am giving you some  fixes that might help you out getting your wifi greyed out or dim get fixed! easily

My Environment:-

1. I noticed that after an update, my phone no longer asked me to select a wireless network. The WiFi Button was grayed out and could not be moved or bothered.
2. i have an i phone 4s and running on 6.0.1
   

Here some of starting fixes i applied to get rid ot the greyed out WiFi

• First fix:-

Create a backup of your i device if you have something important that you might need .
Restore your iPhone and reset all the settings .and after that reboot your iPhone and than just let it be for some time .

Settings>General>Reset>Reset All Settings.

Note:- Reset your iphone when you battery is running less than 40%

• Second Fix:-   

If you sense that you phone is  heated up . That might be another reason that your WiFi is not working for that you must first check the top left corner or your iPhone or below your camera that's where your wifi chip is placed on the motherboard.

if yes! then you WiFi chip must be dried out because of the over heating and all you have to Do is that  switch off your i device and place it in the freezer. and place it there about 30-45 minutes not more than that.
that freezing or cooling will help wifi chip to continue the flow and the dried out chip and the bluetooth chip will start workinh probably.

• Third Fix:-

if your i device is having the WiFi address but only the wifi button is greyed out like in this image . well that's a good news for you i just your Network settings need to be Reset.

  Settings>General>Reset>Reset Network Settings.

Well frankly i tried all above but in my case the freezing one worked. but i got an another iPhone of my friend running on 6.1.3 but unfortunately  i tried all these on that but didn't worked for that.

1. Restoring   phone - FAIL
2. Resetting network settings and all settings - FAIL
3.  Refrigerator technique - FAIL

 So for many sources and After watching many videos at you tube  i applied the final fix on that device and you won't believe but that actually did work!

• Fourth Fix:-

1. Back up your iPhone. If you have a jailbroken iPhone, create an SHSH Blob on Cydia to preserve your jailbreak. 
2. Write down the WiFi or MAC address of your bluetooth and your wireless. If you have no WiFi address or it is something odd such as 00:00:00:00:00:00, don't worry.
3. Jailbreak your phone using evasion. You may use other tools, but since my iPhone is updated to the latest iOS, I am limited in what I can use.  http://evasiondownload.org/ 
4. Download ifunbox or ispirit for insatalling ispirit you must have microsoft framework 4 and itunes 7.1 or newer version. To get apps on to your phone through your USB cable.
5. Using iFunbox, search, download, and install macx4.
   
6.  Now see your Phone you will find a new app named Macx4 open it and Hit the "Restore Original MAC" found in MacX4.
7. Your iPhone  should reboot. If it has successfully restored the wireless, it will ask you to set up your iPhone as a new phone. However, everything will be exactly how you left it. I assigned my iPhone bad MAC address causing it to lose its wi-fi and then I successfully restored everything using this app. 

well in my case it worked for me and i Hope you find this helpful.

Thank you.