The first thing I'd recommend you do is reconnect the digitizer and LCD cables to diagnose the issue. After you've done that, if you're still noticing touch issues the last thing it could be is the screen itself. Touch ic is located on the screen so It may be possible it got damaged in the process. Only other way to diagnose the issue would be to get a new screen and test it.
Hello. So, the iPhone has 2 microphones. One inside of the ear speaker grill and the one on the bottom of the phone. The one on the bottom of the phone is the one that is ONLY used for phone calls and Voice memos. FaceTime and talk to text is all in the microphone that's in the ear speaker grill. So if you have no issues during calls, the problem is going to be the microphone in the ear speaker grill.
Sounds like you got a defective battery. Usually what's recommended to do with new batteries is charge it to 100% let it die, then again, charge to 100% then let it die. But in your case, could be a faulty battery or maybe you didn't connect the battery correctly. So the 10 seconds that it's on, it uses whatever power is still in the laptop
it sounds like it could be the TouchIC chip, Ill leave a link to a picture of it, a way to find out if it is the TouchIC chip is by putting pressure, it makes the connection with solder points, so if when you put pressure, thats the problem. https://i.ytimg.com/vi/5YgPUEqVqrA/maxre... The touchIC is the square on top of the sim card slot
It's the screen. The connector is not fully making contact with its connector. When putting the connector down, run your finger from let to right to ensure all the pins are making the connection. You should hear 2-3 clicks