What’s my issue: I/O Board, I/O Board Flex Cable or Logic Board?
My MacBook stopped charging one day, and the Apple store said it was due to corrosion around the I/O and/or main logic board and likely there was no hope to fix it. I was told it was probably moisture got drawn in through the fan... to clarify, I’ve never spilt anything on it.
Anyway, I decided to try repair it myself as it’s out of warranty and I got quoted £550+VAT for the repair! I’ve dismantled it completely and carefully cleaned all the components with 99.9% isopropyl alcohol. I did notice some slight corrosion on the underside of the logic board. After drying it out, I’ve reassembled it.
It still won’t work, however I’ve noticed that if I plug in the MagSafe charger (no light shows) and unplug the I/O flex cable, the fan runs and the computer starts up and I get a weird screen (will try upload a photo).
But with the flex cable connected, absolutely nothing.
Long story short, can I determine if the damage is to the logic board, the I/O board or the I/O cable?
I've managed to get my MacBook to turn when plugged in and the I/O cable is not connected. I still get no light on the Magsafe charger, and the computer is running slow with no audio etc, however I can still use it pretty much as normal. As soon as I connect the I/O flex cable, the computer turns off. Likewise when I disconnect the power, it does the same.
Does this sound like an issue with the I/O board itself perhaps?