Chris Stables

Did you transfer the home button flex cable over from the old screen? If it works on one screen but not the other it is defiantly flex cable related.

I would check for long screw damage on the left bottom screw hole. LCM_TO_CHESTNUT_PWR_EN and PN5V7_SAGE_AVDDN run under there.

I think you will find they are just reflowing the ic instead of removing it, running jumpers and reballing. Reflowing the ic is only a temporary fix.

If your home button was working before you changed the battery and you didn’t remove the home button from the screen the most likely explanation would be a really fine tear in the home button flex. It might be hard to see but if you could put it under a microscope I am sure it would reveal itself. I am not sure if iFixit supply the home button flex or not.

Yes. You will need the original home button for touch ID.

First I would try another battery but you probably don’t have one so try opening the phone back up and put pressure on the battery flex connector and see if it charges if it doesn’t there are two mosfets near the connectors that may have been pried. Either way I think you will need the services of a microsolderer.

The problem will be your touch connector. Make sure it is seated properly if it is I would check the connectors with a magnifying glass. I don’t suppose you have another screen to test?