John Bundred

I've done a screen replacement and the home button does not work. Bought another screen replacement and still the home button doesn't work. I've covered all the contacts with tape as instructed but even with the screen outside of the case still no joy. As I've tried two screen from two different sources, have covered all of the contacts and it doesn't work outside of the case I'm assuming I have a different problem to contacts being shorted or faulty buttons. Can anyone help? PS the home button worked on the original screen before I took the screen off.