Chosen Solution
Hello I’ve replaced the whole display from my Iphone 6. I didn’t disconnect the battery, so I put the flex cables in turned my phone on and it worked perfectly, then i wanted to put the metal shield on and afterwards my phone wouldn’t turn on anymore. It doesn’t find it on iTunes, I tried again and again the cables are in the right positions, the screws where never mixed up or something I also tried the restore mode and dfu mode nothing. When I put my phone on charge it gets warm so I think it’s still alive? Thank you very much for every help!
Based on what you say, it does appear to be related to screwing the bracket back on. Ideally you should always disconnect the battery but I don’t think this is your problem. Even if you didn’t mix up the screws, if you over-tighten them you can still cause damage to the logic board. Try to remove the bracket again and see if the phone works. Inspect the connectors with a magnifying glass or jeweler’s loupe. Get back to us with your observations.