OMG, it WORKED!!!!
Thank you Highonlife! We were JUST about to head to the apple store and fork out $$ for a phone that was JUST over a year old, but we tried the heat/cooling technique at the link you suggested
Gee. I would hate to be so cynical to think that this is a software scam. This should be brought to the attention of MacWorld.....next thing on my list....
Same problem as listed.. I tried the blow dryer method, and I got the wifi back for about 5 minutes. The phone auto-shut down and upon reboot, the wifi was greyed out again.. I really believe it's a firmware issue, and although these quick fixes work, they are temporary. My problem began after the latest iOS s/w update 7.0.6.
Had the same problem (WiFi grayed out, no wi-fi available) all of a sudden today. I tried the network reset - no change. I was planning to try the Apple suggestion of resetiing iCloud and started by going to Settings - iCoud. I turned off everything in iCloud, including Find My Phone and when I went back to Settings, I saw that my wi-fi was trying to find a signal. It found my network and it's working again.
I have since turned Find My Phone back on and it all works.
iPhone 4S, out of warantee (of course); hope this helps someone.
I tried a number of these things to fix the greyed out wifi on my iphone 4s. The freezer thing worked for about 5 mins, but they got heated up and stopped working.
When I took it to the genius bar (in Vancouver, Canada), they said nothing was wrong with my phone in terms of hardware damage and they could do nothing but suggested I get a new phone.
I want apple to sort this out with the iPhone 4s. I think there is enough iPhone 4s users that shouldn't have to get a new phone souly because they updated their phones and the updates caused they're wifi to stop working. This is an apple problem. Also, when I've looked through the apple website to contact apple to share these thoughts... there is no where I can email... Seriously need a suggestion box somewhere on the website and don't tell me I have expired applecare so no help there.
I've only had the device for 16 months (warrenty only good for 12 months). If iPhones aren't build to last they are crappy phones and I'm done with them.
I tried something even simpler and faster than the heat treatment and it worked--at least for me. I have avoided upgrading my iPhone 4S to iOS 7x, and yesterday I found that for no reason the WiFi switch on Settings was greyed out. I followed a suggestion posted on the first page of this thread from Istanbul and simply reset the network settings. It worked! Go to Settings, General, Reset. Select Reset Network Settings. The phone turns off and then restarts. WIFi is back again!
I'm a mac user and fan dating back to the 80's as well as a share holder and honestly Apple should be ashamed of themselves for how they're handling the iPhone 4s wifi and bluetooth greyed out / non functioning problem. As many have concluded the update to iOS 7 has rendered thousands of 4s's virtually useless due to how the update is making the wifi chip (which manages the bluetooth functions) overheat telling the system to shut them down.
They keep claiming it's a hardware issue--which isn't exactly true. Apparently the software update is making the hardware run hotter than it should. Then the software is shutting down the wifi and in my case the bluetooth functions. Resetting the network configurations didn't work. The freezer remedy only solves the problem for a short time. Until Apple provides some kind of fix voluntarily (as they should to loyal customers) or is forced by a class action lawsuit and subsequent recall (hello, where are the greedy attorneys when you need them. ;) the best fix I could find after 4 months of scouring the web are these videos made by an iPhone 4s customer who had the exact same problem. He even went as far as to secretly video tape his interaction at an Apple store as well as report his experience to the local NBC news affiliate:
Apple store meeting (identical to the experience I had with Apple): http://youtu.be/0DwY452C_sw
This fellow provides a briefer explanation with a disclaimer that it may not be permanent:
Hope this helps
Just got off phone with apple:
1. Reset Network settings
2. Toggle airplane mode
3. Turn on/off device
4. Restore to factory settings
5. Still did not work. No wifi or bluetooth.
Their suggestion: Since you are out of warranty, it has to be your device and not their upgrade. You have the option to buy a new one or get it repaired for about $199. Seriously, that was their resolution to a problem they caused.
I too was having the same problem with the iPhone 4s. My wifi and bluetooth went out about 3 weeks ago. After going to the Apple store, calling Apple and talking to an Apple representative online, I received the exact same response as everyone else. The phone is about 3 months past the 1-year warranty and I don't have Apple Care, therefore my only option according to them was to replace it for $199.00. I finally figured I would try to hairdryer and freezer trick because I had nothing to lose. I tried it once and it did not work, but I didn't wait for the temperature warning to pop up because I was worried it was already too hot. When I did it a second time and waited for the temperature warning on my phone, it worked! I was amazed that it really did work. I still can't believe Apple is denying that there is a problem with the phone. It is sad that we have all paid quite a bit for these phones and we have to try to fix them ourselves. The Apple representative that I chatted with online today said that the flaw is not affecting enough people for Apple to issue a repair program. He stated that "out of the billions of iPhones out there the issue is less then .3%." If you calculate .3% of one billlion that is 3 million people who are being effected by this flaw. Seems like a lot of people to me.
The WHY and HOW to repair the Wifi and Bluetooth issue with iPhone 4S
The problem is a hardware issue, NOT software.
The reason your wifi goes from working in one version of iOS to failing after an update is because the new iOS version checks the wifi chips functionality before allowing the OS to use it. If it doesn't pass ALL tests, it will not allow wifi to switch on in iOS. The older version of iOS will simply not check the wifi chip for faults and just go ahead and use it.
The problem is the solder joints connecting the Wifi IC to the circuit board fracturing *some* pins. But it often has enough connected pins to allow iOS to operate it without passing all tests. It just won't work with iOS7 which will reject it if any diagnostic pins are not connected or fractured.
Why does it fracture? well, this is a common problem with BGA mounted ICs on a lot of electronics since the banning of lead content solder. The non-leaded solder is more prone to fractures under heat. So we have gone "greener" but sacrificed reliability in the process.
How do we fix this without reballing it with LEADed solder?
REFLOW the Wifi IC
the best way is to use an infrared rework station, but that is uber expensive and out of reach for most people.
An alternative is to use a hot air reflow. While it will do the job, I feel it is not actually the best way as it uses more heat than is necessary and is prone to damaging surrounding components and warping.
The best practical method available to the average person is to reflow it in an oven.
I use a small electric toaster oven, which I use to reflow laptop motherboards, PS3s, graphics cards, DRAM modules, phone and tablet boards and so on.
remove the 4S motherboard and wrap it in Aluminium foil leaving only the wifi chip exposed. Remove the black sticker shield on the wifi chip. The Wifi chip is the large square IC near the headphone socket.
Put the wrapped motherboard in the oven and, HERE IS THE SECRET SAUCE, put a small strand of solder about 5mm long and bend it into a 3D roundish S-shape. This is your temperature guage! Put it on the insulated foil near the area to be reflowed.
The biggest problem with reflowing is getting the temperature and timing right and using a piece of solder as an indicator gets the best results.
the Solder will melt at around 220deg C so set the oven to around 230-240.
after 5 to 10 minutes depending on the power of the oven, you will see the solder slowly melt and fuse into a ball.
start a stopwatch when it turns into a ball blob and give it 60 seconds and turn the oven off and open the door.
this allows the right temperature range to hit the spot to reflow the solder joints without overheating anything.
everything on the motherboard can withstand this temperature range because all of it had to be mounted at manufacture with AT LEAST this temperature.
DO NOT MOVE THE ITEM WHEN IT'S HOT
allow it to cool down to room temperature.
after it has cooled, unwrap it and put it back into the 4S.
Wifi and Bluetooth will now work without resetting anything or restoring.
There is no magic special way around it, the Wifi Chip needs to be reflowed. It is not a software problem.
And it will work after the next iOS update or restore unlike the blowdryer method which is just a temporary workaround to bypass the IC testing. With regards to freezing,all it does is contract the unfractured pins and try to pull the fractured pins together to temporarily press the fracture together. Freezing can fracture more joints than it can repair so it should be avoided unless it is the only method available. You want to repair it for use at room temperature, not for use in the antarctic.
If this is useful, I can start a new thread and write up a proper step by step with pictures.