When starting to diagnose this Nintendo Switch it would charge but nothing would show up on the screen. When I opened it up there was obviously liquid damage and whatever the liquid was left things pretty gross. Also, I could tell something had it apart already and had not put things back correctly. I spent quite a bit of time cleaning things up. I also reconnected a capacitor and replaced the game card reader. My Nintendo Switch repair videos: https://www.facebook.com/watch/1394635077450140/148

How to Fix Software Update Error Nintendo Switch - Full Guide