Chosen Solution

I cannot turn on the WiFi on my iPhone 4S. But every time I remove the back cover, the WiFi works. When I put the cover back on, within a couple of days the WiFi is greyed out again! I cannot see anything wrong with the iPhone.

If the WiFi only works when the cover is off, then it suggests a physical problem.The back cover is either warping the contacts or preventing the signal from getting through. Take a look at the midframe. Is it bent? Has the phone been dropped?

I’ve seen this issue quite a bit. It’s definitely not software related, but hardware related. What you need to do is:

  1. remove the back glass and unplug the battery and remove it.
  2. Remove the Emi shield that covers the LCD connector
  3. inspect the board and you will see a black big chip (the wifi IC). Looking straight down with the charging pins closer to you, it’ll be on the right.
  4. THE FIX - you need a hot air type of tool. I’m not sure if a hair dryer will do the trick, but I use a heat gun. You need to apply slight amount of heat. NOT a lot. Just enough to get it hot but not too hot (too hot = you can’t touch) like I said, slight heat.
  5. put the phone back together and voila. Works! I’ve seen roughly 3 phones already same issue same fix. No warranties so far.

I can confirm that YoloRepair’s fix does work. I did it on my phone today that had the greyed out Wifi issue. I want to add and clarify a few things that might help the next person: Watch this video before doing anything: http://youtu.be/ZHH-zbNgJx0 You don’t need to follow all the steps, just the ones on how to open the phone, disconnect the battery, and remove the EMI Shield. That’s all you need to do to disassemble. You will need a pentalobe screwdriver to open the phone and a spudger definitely helps with prying and whatnot. You can buy them both of course on iFixit. I disassembled and using a hot air station, put hot air on the wifi chip and heated the surface to almost 400 deg F. I used a heat sensor to read the temperature as I was heating it up. It only took maybe 5 seconds. I would strongly recommend this method over a heat gun as the air temp is easier to control and put down on the chip. You don’t want to heat anywhere else, and you don’t want to overheat and potentially blow the chip or other components off the board. That is it; i reassembled and wifi turned on and has stayed on and has stayed connected thus far.

restore the phone. if it does’t work, take it back to the apple store.

I’m having trouble identifying the tabs mentioned by Austin Harris and gjlecointe. I am looking at the following pages: iPhone 4S Teardown iPhone 4S Screen Replacement Can someone point me to the specific grounding tabs to check?

I am not sure why, but I took the Otter Box off and squeezed the case a few times and it worked! That was after the restore that failed to fix the problem. I am now convinced the grounding issue is the cause. Stay tuned……. Update…does not work properly yet. The settings screen shows WIFI off, but when you access the WIFI option it shows “on” and searching for network, but never finds one.

I had an issue like this a few weeks ago. When I reconnected the black wifi cable I slightly disformed the silver round receptacle on the logic board. I used a pair of small needle nose pliers to repair it. I also thoroughly cleaned the antenna wire and receptacle (99.9% alcohol and a softw cloth wipe)… (They can be a pain to get reconnected sometimes, you know, twist, snap, twist). Another problem, if you can’t resolve it with all of the above great advice from others, is a potentially flaky wifi antenna chip. Their could be a stress break in a solder joint and by applying and removing pressure creating a temporary connection. http://www.parts4repair.com/iphpne-4s-wi… thanks to OldTurkey for that link a while back when I was searching for a power ic. :) good luck!

Ok someone told me to take a hair dryer and use it on the earbud plug. I set mine on the counter since it was too hot to hold and with the phone on direct the hair dryer in the headphones jack until it goes into the too hot phone needs to cool down screen. Then once it does go back to the reset all network settings screen then bam! It works. We have been having problems with iPhone 4S and since the hair dryer fix it’s all good. Wish I could remember who told me how to do this cus I would thank them

There could be several issues causing this. If you’ve already tried the basics such as restoring (which i doubt will help) then you should check to make sure the wifi grounding chip is in place along with its corresponding screw. They’re located at the top inside of the iphone where the 5 screws go together to hold down the plate covering the lcd/digitizer/power button flex cables. The top LONG screw needs to be in place as well as a tiny seemingly pointless piece of grounding metal on the back of the plate cover. I cant seem to find a picture but if i do, ill post it for ya here

Austin is on about the iPhone 4 the long screw for the wifi is not the same in the 4s the 4s has a component that clips in

Tried all the apple suggestions and in the end asked O2 to look at it, they wanted to charge me £136!! I decided to change to a HTC one which is a much better phone. Anyway now I didn’t need the iPhone 4s I tried a solution I saw on utube. Turn the phone off and wrap the phone in a cloth and put it in the freezer for 20 mins. Take it out and switch it on and you wont believe it but it now works, WiFi is on and connect to networks at home and at work. No idea why cooling the phone fixes it but who cares it’s now for sale on eBay!!

there is a prob with the wifi chip.. either you have drop it down or the heat sink has been damage due to overheating

This fix worked on my 4s. Dropped it and broke the back glass. Noticed the wifi went out the next day. Replaced the glass via amazon and then disassembled to point of accessing the wifi chip. For heat, I used a butane torch with ‘hot air’ tip so it isn’t direct flame and just heated it till I could just hold my finger on without burning (I don’t have a thermometer to test). Reassembled and bam! Works. Many thanks!!!

Yolo’s repair trick by heating up the wifi chip for about 15 seconds up to around 400 degrees F does work, but it seems to be only temporary because Apple has not corrected the iOS 7 programming program..which is the root of all the problems it seems. I followed Todd’s advice and only took out the battery and the EMI shield…..isolating the heat source to the wifi chip as much as possible does not hurt. I had to repeat the process two weeks later because it most likely overheated again. Thanks for the great tips!

Had the same problem after updating the software twice recently. I tried everything from resetting network connections, updating/syncing with itunes, switching off airplane mode, factory reset, etc. etc. I put it in the feezer and this fixed the problem for only a few hours. I then tried the hairdryer and it only worked for a few hours too. But then I read that you need to get the iphone really hot and focus on the top right section of the front of the phone with the hairdryer. I used the hairdryer for 3-4 minutes and the phone was quite hot. I read the hotter the better but I didnt want to risk too much heat. But it was hot after this. I immediately switched on the iphone and my wifi signal was better then ever. After a few weeks I then received another ios update and decided to chance the update a few days ago. I immediately lost the wifi again but repeated the hairdryer treatment and once again wifi back and working really well. So, try it and see. Definitely worked for me. Lingmell.

Genius Bar gent told me that this is a hardware problem that Apple is having randomly with 4s phones. I had backed up yesterday. He smiled took my phone and produced a new 4s that works fine (at least so far). Whole problem resolved in 10 minutes. Friendly and apologetic.

Hair dryer trick has worked for me 3 times now. Each reset has lasted about a week. Apple insists its a hardware problem and since the phone is over a year old won’t replace it without paying full retail. Not happy with Apple at all.

http://www.iphoneincanada.ca/how-to/fix-… guys this is the solution its working and well working without any issues

The blowdryer method is actually working. Had stable Wi-Fi connectivity for 5 days

Well I posted this this issue and I’ve tried everything even the Canadian hair blow drier solution :) Nope I still have a grey wifi :( so I came to the conclusion that I have a DEAD wifi chip on the MB :(

I just turned my phone off. I let it rest for minutes then turned it back on. Wifi is not greyed out anymore but I still can’t connect to any networks. Everytime I try to connect to a network it will only tell me that it is unable to do so. Then, whenever i tried to turn it off, my screen would freeze. I guess I just have to drain the battery totally and let it rest for hours, or days, then I’ll try if it will work again then. With hopes! UPDATE It doesn’t seem to work. Guess I’ll have to do something else then.

Its almost as though the phones are programmed to stop working so you need to pay for a replacement or upgrade.. This problem is all over the internet, most time there is no reason for it, phone isn’t hot or even warm. In most cases the phone is literally not even being held. Ive seen this all to often to be just a technical fluke. I’ve worked for Bell mobility, Telus mobility and ive seen this probelm atleast once every 2 weeks, some weeks ive seen it up 4 -7 times. And it always seems to be between 1.5 - 3 years of the person owning the device. I can accept that it could be a faulty transmitter and reciever but it happens accross all iphones and not just the older models… Why do people have to pay for a replacement when its clearly a manufacturer defect? This is unacceptable to me. Just another cash cow, weather it was intended or not. I currently work at sasktel in canada (cell carrier) and i was helping a lady with her personal hotspot and the BT and WIFI stopped working right in the middle our session.

I can vouch for this heating method. I purchased a 4S with greyed out wifi, and n/a for the wifi address under the settings. The bluetooth was showing an address under settings but would continuously be initialising itself. I removed the back, battery and EMP shield as per the instructions above, and warmed the wifi chip with the tip of my soldering iron for a couple of minutes (I don’t have a hair dryer). I re-assembled the phone, turned it on and BAM….the bluetooth was on straight away. I went into wifi, which was now no longer greyed out, selected my router and connected. I can turn the wifi and bluetooth on and off and they connect successfully every time. 100% perfect result!

Hi All! This heat treatment trick worked for me too! I had the same issue with my 4S. Resetting the network setting didn’t work. Neither did the freezer help. Then I went on with the heating trick. Actually, I tried an easier version, found on YouTube:

  • I left my iPhone switched on.
  • Took my hair dryer on maximum heat settings and started to heat the phone around the earpiece / front cam area on the top.
  • I did this for a few minutes until my phone displayed it is overheated and needs to cool down before use.
  • Turned it off and waited for it to cool down.
  • Then I turned it on and wifi was back! Awesome!

nem com o secador de cabelo meu iphone 5 volta a funcionar o wi fi.. alguem ajuda, contato no email joao0504@yahoo.com.br

is there no chance to fix this with a software? i mean to bring the ipohne to the temperature mode without heating it up? i dont think its good for the other parts to heat it up

Please help, i got iphone 4s with wifi grey, after reflow wifi IC phone wont turn on. What did go wrong?