Hi i am a STEM student (not electronics but I have some basics) and I like tinkering with electronics. I have experience soldering but not microsoldering. My friend came to me with his broken 2019 Intel macbook pro and I offered to help saying i'll do what i can. He said some sticky liquid from a desert spilled in his bag and got in through the right side (the one with the touch id). I managed to advance a bit but hit a real roadblock which is why I signed up for this forum. In terms of tools I have access to a multimeter with diode mode, openboardview with the relvant schematics, a microscope, an ultrasonic cleaner, iso 99%, screwdrivers and hot plates. All of these are froms various labs on my campus.
I first tried to turn it on and nothing happened. I decided to open it up and saw that some parts had corrosion on them:
I tried to clean it manually and saw that and with some iso 99% and a cotton swab and see if it changes anything. Here is the photo after the cleaning:
I then held down the power button. It showed the no battery but the display did light up. However after closing it up the display no longer showed anything even when plugged in. I decided to use an ultrasonic cleaner In which I put warm distilled water and a bit of 99% iso because i didn't have acess to any special solution. When i took apart the board to clean it completely I discovered that another area on the underside of the motherboard had corrosion:
After putting it through the ultrasonic cleaner (both sides for multiple minutes) the board seemed more or less clear of corrosion, i dumped it in alcohol and moved it around for a bit then let it dry for a few days:
After it was dry I put it back together (replaced the thermal paste). And tried turning it on. I had no display but the caps lock did light up. I used a usb-c to hdmi to plug it into an external display and got the question mark folder. I managed to restore it over the wifi connection and then it booted into the os. My friend logged in and recovered the files. It now boots fine. The only problem is that the internal display doesn't work, and I am stuck trying to fix it. I tried investigating the J8500 with the multimeter but wasn't even sure what to measure. I think the problem might be related to U9850 since a lot of gpu connections seem to go through there but obviously I don't really know what I'm doing so I am very likely wrong. One thing I can say is that the internal display is fully black, so i don't think it's a backlight issue, at least not solely. I found this forum and decided to sign up and post this thread in hopes of getting some guidance.
I first tried to turn it on and nothing happened. I decided to open it up and saw that some parts had corrosion on them:
I tried to clean it manually and saw that and with some iso 99% and a cotton swab and see if it changes anything. Here is the photo after the cleaning:
I then held down the power button. It showed the no battery but the display did light up. However after closing it up the display no longer showed anything even when plugged in. I decided to use an ultrasonic cleaner In which I put warm distilled water and a bit of 99% iso because i didn't have acess to any special solution. When i took apart the board to clean it completely I discovered that another area on the underside of the motherboard had corrosion:
After putting it through the ultrasonic cleaner (both sides for multiple minutes) the board seemed more or less clear of corrosion, i dumped it in alcohol and moved it around for a bit then let it dry for a few days:
After it was dry I put it back together (replaced the thermal paste). And tried turning it on. I had no display but the caps lock did light up. I used a usb-c to hdmi to plug it into an external display and got the question mark folder. I managed to restore it over the wifi connection and then it booted into the os. My friend logged in and recovered the files. It now boots fine. The only problem is that the internal display doesn't work, and I am stuck trying to fix it. I tried investigating the J8500 with the multimeter but wasn't even sure what to measure. I think the problem might be related to U9850 since a lot of gpu connections seem to go through there but obviously I don't really know what I'm doing so I am very likely wrong. One thing I can say is that the internal display is fully black, so i don't think it's a backlight issue, at least not solely. I found this forum and decided to sign up and post this thread in hopes of getting some guidance.