I've got this old iMac that I'm trying to get up and running again. When I hit the power button, the fans kick in and I...

I encountered a comparable issue with two separate iPhone 8 devices. While attempting to disconnect the battery and throughout the repair process, I accidentally made contact with the logic board, causing damage to some of its components. As a result, the iPhones failed to charge properly in both cases and remained stuck at 1% battery, besides being on a boot loop. I decided to seek help from a micro-soldering expert, who successfully repaired the devices. Probably pry damage... manipulation.Pry damage (Signs and Prevention)