Chosen Solution
So I replaced my IPhone 7+ Screen last night. I was very careful with the flex ribbon but at time I felt a little rough with it to get it off the sticky part. When I turn the phone on it reboots itself after a few seconds. Sometimes It will stay on for a few minutes but once you make a call there is no audio and the phone just crashes. HOWEVER, the camera works great.. Do I have a bad flex? I feel like if the flex was bad the camera wouldn’t work. I can order a new flex for $25 on amazon, I just am skeptical because half the people say they work and the other half doesn’t. I don’t know if the flex is bad, though the camera works, or the earpiece is bad which is causing it to crash. I unplugged the flex so the phone can be used for the time being I just have to use speakerphone to make a call.
If the phone works fine without the flex connected, then definitely change the flex cable. You should inspect carefully, preferably under magnification. You may have created a tiny tear in the flex or dislodged the proximity sensor. You can find the replacement guide here and a replacement part here.
