Over the years of repairing iPads I’ve seen multiple iPad 2s do the same thing. Not sure what the exact cause Is , but it appears to be a logic board failure , maybe ram or the A5 processor. The iPad may be good for parts now , but not much else as there’s no know fix other than replacing the...
The 1st gen ipad is 9 years old now so odds are it is the battery. But there’s no way to be certain until you try a different battery. The 1st gen ipad is a huge pain in the ass to remove the screen though.
Are you certain the lcd was plugged in properly prior to reassembly?
Also check for a faint image with a bright flashlight against the lcd. It’s possible the backlight isn’t functioning
Make sure you are using at least a 10 watt charge brick , preferably the official apple one. The smaller iPhone brick will not work. Also check inside for damage or dirt in the 30 pin connector. Sometimes the corners can break off If the cord isn’t inserted properly. The charge port could be...
What twerppoet said. This will show if there are dead spots in the digitizer screen. Use your finger not the pencil as each one uses a different method of detection
Not great but not horrible either. You may also want to consider her far you are from your router when the web pages load slowly. Are you in the same room or the opposite side of the house ?