Baseband issue fixed when wifi disconnected

I've had the constantly "searching" issue with my iPhone coupled with the not recognising there is no sim installed and no modem firmware details or imei details showing up in the settings menu. After much googling and trying to find a solution, I stumbled on a temporary fix but don't understand the logic behind it. I was trying the stick the logic board in the oven on 180 for 20 minutes fix which is suggested in many places. After this had been done I reassembled the iPhone and voila, the modem firmware details were displayed and the phone found and locked onto my providers network. I noticed however I had no wifi. I took the phone apart and noticed I hadn't plugged in the wifi antenna properly. I corrected this, reassembled and switched on. Wifi was back up and running but the baseband issue was back. I wondered if the wifi was causing the issue so I opened up the phone again, disconnected the antenna, reassembled and switched on and once again the phone locked onto the network. I repeated this several times, each time the wifi antenna was plugged back in, the baseband issue returned.

I am at a loss to explain this, can anyone help and suggest which but if hardware needs replacing for a complete fix where I can get the wifi plugged in and baseband issue fixed?