Chosen Solution
Iphone was kicked few times. I changed battery and screen with home button. Then i turn it on and everything was fine. Next I changed front camera it was turn on but itunes did see it. After that apple logo start flashing. I tried itunes recovery and 3utools and its 4013. I’m not sure wheres blame. Charging dock or front camera was faulty and its broke motherboard. I red front camera could to this ?
The iPhone 7 series is known to have issues with the front camera flex, so that is most likely the problem. Try disconnecting all the non-essential cables and see if it turns on normally
