Chosen Solution
I Replaced a screen on this particular IPhone 7 Plus with no issues , Then it needed a battery replacement. Replaced the battery and now i have no home button nor Touch ID. Any help would be greatly appreciated. Everything else works with no issues.
So you transferred the home button to the new screen and reassembled the phone and the home button and touch ID was working. Then you removed the screen again to replace the battery and now the home button is not functioning. There are two possible causes. · Check the home button connector is seated on the logic board correctly. · Check for a tear in the home button flex cable. (The one that goes from the screen to the logic board) You might need some magnification to detect it. This is the most common problem.
This post should help you out on the issue, they did a very good job on explaining it too. iPhone 7 home button not working after screen replacement In my view you may have damaged something when you replaced the battery. You should take the device apart again and see if you put the ribbon cable in correctly.
