Lcd sometimes works, but most of the time doesnt work
I have a iPhone 6s that has a shattered glass. the phone its self is still on and making phone calls, receiving calls, makes noise and everything, but nothing was showing, so I thought the lcd was bad. I got the replacement lcd and tried to test it but it still didn't show anything. From this point I figured there was nothing I could do so I put the old cracked lcd back on the phone and put it back together. I put it on charge afterwards and was kind of playing with it, but then the cracked lcd screen came on and was working really good. But then at random, the lcd would go black again. so I put the new lcd back on it and it worked good for a few minutes, but then again the lcd went black agian. if I reset the phone, it will start working again, but it will stop working once I receive a phone call or make a phone call, sometimes. I have no idea what the problem is and I really need solution quick. Please!!