Touch Not Working after Digitizer & FPC Connector Replacement
I’ve got an iPad Mini 3 WiFi (A1599) that belongs to a friend of mine that I'm working on. A few months back they dropped the iPad and it cracked the digitizer in the top right corner by the power button. They asked if I would repair it which I agreed to do. I replaced the digitizer and all was well.
A couple weeks ago they called and told me that the Digitizer was starting to lift in one of the corners. I told them no big deal and that I would re-tape the digitizer. This was partially my fault as I should have re-taped the replacement digitizer with my Tesa tape when I originally installed it, instead of leaving the garbage adhesive that came on the digitizer. But I despise working on iPads and just wanted to get it back together and off my workbench as quickly as possible. =p
So I got the iPad a couple days ago and disassembled so that I could remove and clean the old adhesive. I applied some new adhesive and proceeded to test fit the LCD & digitizer so that I could do a final test before final re-assembly. At this point I booted up the iPad and noticed that the Touch wasn't working. The Home Button and everything else was fine, but the digitizer was not responding to touch. So I attempted to re-seat the digitizer connecter when I noticed that a couple of the contacts were missing from the Digitizer FPC Connector. I replaced the FPC connector with a new one, booted up the iPad but still, No Touch! I swapped the digitizer with another one I had lying around but still, No Touch!. I also checked each leg on the FPC Connector with my multi-meter, and each one is making contact with the pads on the board, so I’ve ruled that out also.
I've never come across this issue before and was wondering what else I can check and/or replace to get the touch working again. Perhaps an IC or filter that maybe got shorted out when the FPC connector pins came loose?
Thanks in advance.