Chosen Solution
Hi Community I replaced the battery in my iPhone 12 and now my phone doesn’t have working cellular. It might occasionally give me a few bars but mostly not, also when I tried to update on wifi it said it couldn’t verify my update because it wasn’t connected to the internet even though wifi was fine.I suspect I have done damaged or dislodged something since opening the phone was very difficult and my attempted as removing the old gasket were also difficult so I could have caused damage then. In order for me to at least attempt to fix it I need to know what the most likely component to be faulty is and where it is. I’ve successfully replaced many batteries on older models but i’m a novice when it comes to other parts in these phones so looking for some direction. I have gone back into the phone reconnected everything and gone over it but I can’t tell what might be wrong. Any ideas and pictures showing the potentially offending parts would be helpful.
Did you reseat any connectors other than the ones you needed to remove for the actual repair? First thing i would check is the one immediately above the cable for the earpiece assembly from the screen. That cable looks to be connection for small antenna for a host of various things including WiFi, NFC and some cellular. Part in question is the one circled in the picture, and is typically mounted in the upper left corner of the phone. Could have gotten nudged when you popped out the display connector.
