Settings -> Privacy -> Analytics & Improvements -> Analytics Data -> Search for “thermalmonitord” If there’s a log there that says “thermalmonitord returned not alive” then try replacing the charging port
If you still have that phone try this: Go to the settings app -> privacy -> analytics and improvements -> analytics data -> and look for "thermalmonitord" if it is there you probably want to replace your charging port.
iFixit has this guide: ドライバーの使用方法 Although, it might be your screwdriver, tri wing screws (which are on the joy con) are pretty picky and cheap screwdrivers (eg. amazon or stuff you get with parts) don’t work. You might have some luck with iFixit’s screwdrivers, they worked very well for me.
I have not worked on a google pixel before but here’s what I found out from working on other phones: (1) That shield probably doesn’t do anything, and I haven’t seen a screw that is conductive, I doubt the pixel has one (2) Yes, but you won’t be able to see anything (3) Usually phones boot loop if you don’t have a battery connected (4) Logic board, battery, charging board (you could use the power button instead, although I did this on an iPhone 11 and it wouldn’t turn on) (5) I have no idea, I have never used a multimeter
If you have the tools and think you know how to take it apart, try taking it apart by following iFixit’s guide found here: Apple Watch Series 4 バッテリーの交換 Apple Watch Series 4 スクリーンの交換 (These guides are the furthest iFixit will tear down the watch, the tear down does disassemble it further, but it doesn’t show precise instructions) After this, try cleaning off any corrosion you see with a clean toothbrush and isopropyl alcohol. If you don’t see any corrosion, lucky you. Mine had lots of corrosion everywhere. While you’re in there you can also replace the battery if you want and make sure to replace the screen adhesive, also you might want to fix the screen as well. Keep in mind that the watch likely won’t ever be waterproof again, even with a new screen and adhesive, so be careful not to expose it to water. If I were you I would take it apart to try to clean it, since you have nothing to lose if the screen is cracked and it won’t turn on. You will need a hobby knife (about $10) and a tripoint Y000...