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I recently got a Macbook Pro from my friend who spilled a cup of water onto the left side of the keyboard and he turned it off immediately and left it dry upside down for 4 days. It still didn’t work so he let me see if there is anything I can do. First thing I noticed is that it turns on, and I know it’s on even though screen is black is because the force touch on the trackpad turns on and I can click. The bottom of the computer does get warm but fan doesnt turn on at all. I know this still has a little life in it but I cant seem to get it to boot with the USB installer I made. Keep in mind he took out the SSD so I don’t have an ssd to work with, only the USB Drive. I also opened the computer up and everything looks fine and no compression at all. Any suggestions would be greatly appreciated! Thanks!
It sounds like you have some damaged components on the logic board. While your friend did a gallant effort to prevent the water from damaging things. The fact the battery was still connected may have been the systems down fall. You see tap & spring water has minerals in it which are healthy for you and me, but can cause corrosion as well as allow current to flow across areas which shouldn’t have the high voltages (shorting things out). How about posting some good detailed images of the logic board (both sides) as well as any damaged areas you see. Adding images to an existing answer While it might be possible to repair the logic board it may end up be easier to replace it if the rest of the system is in good shape. Update (04/13/2018) Sadly You’ll need to get a new ribbon cable for the trackpad and a new logic board. Here’s the IFIXIT parts: MacBook Pro 13" Retina (Early 2015) 2.7 GHz Logic BoardMacBook Pro 13" Retina (Early 2015) 2.9 GHz Logic BoardMacBook Pro 13" Retina (Early 2015) 3.1 GHz Logic Board Here’s the needed cable: MacBook Pro 13" Retina Trackpad Flex Cable, Early 2015 - Apple P/N 923-00518
The motherboard is on the inside left part of the Macbook Pro, so the water probably leaked into the keyboard and ruined the motherboard.
The fans don’t spin on this MacBook Pro. With everything but the trackpad connector plugged in, do you get a chime on the internal speakers or does it boot to a question mark folder? If so, then you’re likely ok and need to replace the trackpad cable.
