Power button doesn't work has some water damage/no corrosion
My Macbook Pro had some water damage but I took the back off and saw no corrosion and dried the computer completely before trying to start it up. However when I go to push the power button there is no response, however when the charger is plugged in it has a green light like the battery is full. Any suggestions with what I could do to maybe fix it? Thanks!
If the Book was on when it got wet, it most likely shorted out the keyboard. This cannot be repaired. You'll need to replace the uppercase. Here's how to do it: MacBook Pro 15" Unibody Mid 2012 Upper Case Replacement
Here's the part (no, you can't just replace the keyboard): MacBook Pro 15" Unibody (Early 2011 through Mid 2012) Upper Case
Replacement upper case assembly compatible with all Early 2011, Late 2011, and Mid 2012 15" Unibody MacBook Pros. Includes backlit keyboard, and battery level indicator assembly. — 5 available at 189.95 each.
"Dried the computer completely" should take days, not minutes or hours, no forced air should be involved. Double check your top case to logic board connection. Having a full battery and undamaged charging circuit in no way implies there is no logic board damage.
If you are certain that the logic board and all components are dry you could try using the logic board power-on jumpers. The top case does not need to be on or the machine completely reassembled to do this.
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