Chosen Solution
My note9 dropped into the sea by accident, after disassembly found the battery contact got meld. Is it possible to power on without a battery plug-in?
First, you need to clean off any water damage on the motherboard. Use Isopropyl (Rubbing) Alcohol and an old toothbrush or similar to clean any white or green/blue stuff off the motherboard, then let the alcohol dry off.
