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No change removing finstack sensor. Even if no apparent liquid contact over U7200 gonna have a check on it.

Changed CPU buck regulator which has coffe contact but no dice. Seems that the fin stack sensor got coffee too. Can this sensor reporting wrong value causing the issue?

Found corrosion near to the reed sensor. Cleaned and now it works perfectly. It also fixed blank screen, before the smc always thought the lid was closed so no image. Very strange cos it still showed a white screen. Fixed too anyway.

I think one of the phases of the cpu buck converter got spilled cofee. But it was very hard to pinpoint that. Will order a new buck converter and replace. Seems like that may be the issue. One of the phases a little funky would make the machine turn off.

Yes, tryes to boot and before entering on MacOS shuts off. Same behaviour when working only with the board. No signal of corrosion anywhere. Not having the boardview makes it harder, i'm using 820-3662 brd but is not 100% similar.

Maybe i wasn't clear. Working on the board itself, nothing else plugged. It turns on for some seconds and shoots itse;f off.

Battery disconnected while testing. Looking to what is possibly making PPV5_S4 to power cycle.

PPV5_S4 is power cycling. Now after further inspection it looks like C7372 area might have liquid contact. This cap is on the S5_HS_COMPUTING line.

No signal of corrosion and both keyboard and trackpad are disconnected. Board show no signs of damage at firs glance. Will look more carefully.

The machine had coffee all over it's keyboard but it dind't reach the board itself. Same behaviour with keyboard, trackpad and ssd removed. The problem with this board is that there's no boardview available. But as the board dind't had liquid on it, maybe the damage was caused by a short on the...

Same problem happening again. Will check for the SMC_LID signal and get back with results.

Good point.

The program is board dependant but you can boot in smc bypass mode and with a little fiddling force the machine to write the correct smc.

Just in case anyone has this same question, here's the video where Louis says he used to buy programmed smcs from ebay: https://www.youtube.com/watch?v=zj9RXw6D1H8

Yes, that's what i was guessing. As long as is the same chip and it has apple programming on it it will work. Not board model dependant. And you're right, those chips have a protect bit that erases itself when you try to read with a programmer. F*ck Apple! Thanks for the input!

I remember Louis mentioning he used to buy pre programmed SMC's from ebay. That raised this question.

As far as i know there's only 2 chip that provide smc function on apple's logic boards. But when i'm replacing the smc it has to be from a same model board (of course considering is the same chip)?

Thanks for the input but my suspicion was right. Bad firmware, just installed Sierra on a test disk and it updated the firmware - problem gone.

Other issue: Computer goes to sleep after few minutes even when is told not to in preferences. Bad firmware maybe?

External keyboard and mouse works fine. When trackpad is disconnected fans spin normally. Now keyboard and trackpad only working in the efi boot drive selector. This board got reballed but I can turn off dedicated gpu in efi using fedora/grub.