[SOLVED]2012 Macbook Pro 820-3115-A randomly shuts off

[Mac-N-Sauce]

Previous liquid damage. Getting random shut off's. We can power it right back on. Diagnostic test showed no problems.

 

[dukefawks]

Yeah the worst.....could be corrosion anywhere, under SMC/PCH. Could be a corroded resistor or trace, no way to tell. Nothing I can help with besides saying find the corroded part/trace.

 

[larossmann]

spidey sense says corrosion under the SMC, but no clue without seeing it.

 

[Mac-N-Sauce]

Ok, thanks guys, I will do full inspection and get back to you. Should I gently reflow the SMC area? I promise to remove the under fill first this time Louis!

 

[larossmann]

Only if you agree to not fuck it up this time, and only of it is corroded. Note boolean logic, both must be true! I can't see the board, you can see the board, so you can tell what is corroded.. not me.

 

[Mac-N-Sauce]

OK, liquid hit the Q7812 pin 3 , PP3V3SO_EN_L i have the PP3V3SO_EN obviously since the computer works. I assume the Q7812 is bad, but it is surrounded by connectors. What is the best way of replacing without destroying the surrounding connectors?

 

[Mac-N-Sauce]

Ok, just an update: Pin 3 on Q7812 had a partial connection (hence the very random shut down). Had my daughter remove it by heating the board from the underside. Worked great. She then cleaned area and replaced component.

Another Macbook Pro back in service.

Thanks, guys
This one is done!