Chosen Solution
My wife’s iPad Mini 3 (A1599) was dropped a few years ago and had a cracked screen. My brother-in-law attempted a replacement but touch never worked. My wife would really like to get some files off the device that are not in cloud storage but I haven’t been able to get past the lock screen without touch. I purchased a new digitizer, installed it and touch still doesn’t work. Looking at where it plugs in, I noticed a pin is missing (see picture). Is that likely the issue and is that board replaceable? The goal is to get some files from the device, not have a working device afterwards. Thanks for any help and advice.
This is almost certainly your issue. Good on you for digging this deep into the repair. That pin, according to the documents I have, goes from that connector to the CPU and nowhere else (aside from a test point on the back of the board). These sort of connectors can definitely be replaced, the pin itself may be able to be replaced, or at least rigged so it can be used without replacing the whole connector, but it depends on what the damage is specifically. iFixit even sells this replacement connector. But it will require microsoldering skills to replace. If you do not possess those skills yourself, see if there are any local shops that do board level repair.
So I think I got something for you to get the device open. @flannelist did a very good job finding a replacement connector, but to kinda get you running so you can get the file off your device you can use Siri to turn on Voice-Control on your device so you can use it hands-free. You can use the home button to activate Siri, or use “Hey Siri” and ask her to “Turn on Voice Control”. From there just say “Go Home” and your password screen should appear. Then Just say “Tap [Insert button here]” for each button in the password.
