Digitizer not responsive, even after replacement
I have an iPad 2 64gb 3g. It came in with no damage, (we are a repair company with over 1000 iPads repaired) but the digitizer was completely unresponsive. The device had the stock digitizer and was never repaired previously. We replaced the digitizer, but it, too, was unresponsive. We tried multiple digitizers, with no luck. This same exact issue happened with my personal iPad 4. Digitizer stopped responding, replaced it, still didn't respond, even after a restore. Everything is pointing to logic board, and I haven't seen this issue come up yet.