I agree with Ron. iPad 3 dos not have a ribbon cable. I it is an iPad 4, you should be able to press the home button without having the digitizer completely in place. If it's an iPad 3 you can us a piece of metal to bridge the gap between the two pins on the charging port. Just make sure that the digitizer, and lcd screens are connected to the logic board. I've run into problems from energizing the iPad without them in place.