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I have a Macbook where there was a coffee spill, the mac was tried powering on and not shot off right away :( I took everything apart and there was a little corrosion around where the screen connector “i have cleaned it with isopropyl and nothing to see now. Just to the left of the screen connector there is a little cable witch have some nasty melted plastic . On the cable it says J1. https://ibb.co/fJ7nLk I have tried disconnecting every thing but the fan cable and battery, it does not turn on using power button or the Debug pins. When i connect the mag-safe charger it goes green then yellow with or with out the battery connected. Any suggestions what to do? I have a cheap multimeter any reference measure point i can test? MacBook Pro 13” Retina Display Early 2015 Update (05/18/2017) great, it booted up with the battery and psu and speakers connected “doooo so i could hear the chime :)” . But no lcd backlight Is there a fuse ? A picture of the connector it had some corrosion and some of the contacts are a a bit dark in colour.
And thanks for the help so fare :)
To answer your question, that cable is for keyboard backlight. This being burnt cannot short any important power lines to ground which are required for boot. The 2015 model should boot by itself when the charger is plugged in, only if the battery is plugged in too. Also note the fan does not spin on this model, it only spins when it gets hot. If the CPU is not getting hot (indicating it is booting), remove and check the bottom of the logic board for liquid damage, clean where necessary with 95%+ isopropyl. Take a picture of where the damage is too, in case any soldered components need to be replaced (so you know where the damage is). If it is still not booting after cleaning, and you have not got experience or tools to microsolder, send it to a repair shop who carries out logic board repairs.
