820-00850 No Image On Internal Screen

[brunomotter]

Hello. Got this board with coffee spill. Lots of coffee got inside the screen connector on screen side. The board turns on, generates external display but no internal display activity. I cannot tell if there's no image or no backlight, but I think it has no image. Where should I start? Already cleaned up the mess and replaced EDP cable and tried with known good display, but same result.

 

[tcampbell34]

Liquid damage on LCD connector damaged the CPU, so its most likely not fixable without replacing the CPU. You can check diode mode on EDP_INT_AUX_N to see if it is shorted. Most likely is, because that is the pin that is right next to the LCD backlight

 

[2informaticos]

This is a classic damage, which place the machine out of warranty.
Apple did the best (for its business) placing a data line next to 50V rail.

 

[brunomotter]

Dead cpu even if it gives external video?

 

[2informaticos]

iGPU has different outputs for internal/external video.
The iGPU core is still good, but eDP output (for internal LCD) is damaged.