Chosen Solution
So we had a customer who’s IPhone 5s had (inexplicably) stopped touch. First thought was a faulty LCD but when changed, still would not touch. So we sent away to technician to look at the IC which he fixed and touch came back. We gave the phone back to customer and 2 days later he calls and says that he can’t turn on wifi. He claims that wifi was working prior to repair (even though the touch wasn’t working so couldn’t have checked anything) he said that his Apple Watch was connected to the iPhone hence why he knows the wifi was working. He said he tried resetting network settings and restoring it through iTunes to no avail. I took it back to my technician who denies he’s at fault. But He has looked at it, made sure antenna is connected, changed the wifi flex cable, even changed the Wifi IC but no luck. He says the only other possibility is the U2 IC chip but this could wipe the phone data. Does anyone have an opinion on this please?
To repair touch, you have to work on the board right next to the Wi-Fi chip. He probably reflowed and possibly replaced one of the touch ICs, and by this exposing the Wi-Fi chip to heat. And Wi-Fi chips are notoriously sensitive to heat and may stop working if exposed to lots of it. Another possibility is that a drop caused touch to stop and that same drop caused Wi-Fi to stop by causing micro fractures under the touch IC and the Wi-Fi chip. But you could only tell after restoring touch . Finally, “U2” has absolutely nothing to do with it and besides replacing it does not cause data to be wiped. This is complete nonsense. It is like saying if I replace your fuel pump I may be able to fix your car radio, but your tires may end up flat.
Sometimes if you let the phone sit wifi comes back. Its not the wifi chip itself but rather caps that have changed temperature during heating. Many times letting the phone sit and letting the caps come back to normal functioning temp will resolve wifi issue.
