I replaced both the digitizer and LCD with brand new ones after doing everything by the book when I plugged the battery back in and then plug the charging cable in it just beeps no screen and iTunes will not recognize it if it plug the old broken LCD in everything seems to work the screen gets light and no beeps and iTunes sees it so I tried another used lcd out of another ipad mini same model and that also beeps with no other function I hate to keep buying LCD for this what can be causing this.