Overheating after battery replacement? (Previously water damaged)
I've been getting into phone repair, have repaired a good amount of phones now. I bought an S10e off of someone locally, who claims it doesn’t turn on because it was previously water damaged. Upon opening the phone, it looked like someone had already tried to repair it or has repaired it in the past. The battery was strange, because it was smaller, leaving a bit more space on the sides of where the battery sits.
I bought a new screen because I thought the water damaged it, but it wasn’t the case because the screen still didn’t turn on. I then bought a new battery, and this one actually seems to be the right size. After connecting it, it turned on successfully.
The problem now was that it overheats. When it’s on, it drains fast and the top third of the phone is burning hot. It drains faster than it can charge, I think.
Do I have to open the shields for the cpu and add thermal paste, or open all the shields and clean with alcohol? Or only certain shields? Or is it the new battery? Or do I need to replace the board? If anyone needs additional information, let me know and I can help provide it to find the answer. Thank you.