Why is my WiFi not turning on
My WiFi just says turning on whenever it try to turn it on. Factory reset didn't do anything
I have the same problem with my LG G3. I think it has to do with a failed battery. I ordered a replacement online but does not seem to be a new, genuine product so not a full fix. I find that the WiFi comes on, if I switch on the phone without a SIM card suggesting that both batteries are just not delivering enough juice to run both antennae.
So after looking around the web i think this problem occurs when the phone's tendency to overheat messes up somthing in th wifi ic chip. Now i don't know the full break down of the phone's hardware but I have seen some fixes which involve putting a small bit of thermal pad on the wifi ic chip. I havent tried it yet on my broken phone but im pretty confident it'll fix the problem.
Tldr: Thermal pad placed on you wifi ic chip could help.