Yesterday I met my cousin on the street and she told me her iPhone 5 wifi not working after jailbreak and she was finding a repair shop. I told her I can solve this problem, and actually, you also can solve such problem by yourself.
Factory Reset is Not Recommend
For convenience, someone factory reset iPhone directly. Indeed, factory reset iPhone is a universal way for the software problem on iPhone, and I did found this method on the internet, but I do not recommend. Restore iPhone will lose everything and we have to reinstall many apps. Besides, some ways are much easier and better than restore iPhone. If you have to do so, you can go to the article I wrote some time ago about how to deal with iPhone is disable connect to iTunes issues to learn how to factory reset iPhone step by step.
To the low-level Wi-Fi not working
iPhone wifi connected but not working, wifi discontinue suddenly or other mildly reason, following the below process to see if it can help.
Touch Settings -> General -> Reset -> Reset Network Settings.
It is very simple, but I can't promise it will work. If you are lucky, you don’t need to try the next method.
Re-join the network
Can’t get Wi-Fi to work use iPhone OS 3.0 and later firmware, it's completely grayed out after installing iOS6, and …
Re-join the network is the fastest way to check Wi-Fi issue and resume connecting again.
Follow along for a few tips of re-joining to get iPhone no Wi-Fi fix:
1. Click Wi-Fi after running the Settings app on iPhone 5/4S/4/3GS.
2. The, you can see a blue arrow close to the name of network, tap it.
3. Tap on Forgot this network and tap Forget on the verify box.
4. Return to the previous screen by taping the Wi-Fi tab.
5. Highlight the Wi-Fi network name and rejoin it.
Still can’t get the satisfactory solution? You have better advice? Leave your comments below or join the discussion “I updated to IOS 6 but my WiFi won't work!”