820-00239

[2informaticos]

This board connects CPU directly to J8500.
Very likely dead CPU, because of overvoltage from backlight rail.
No dedicated GPU, so external video missing too.

 

[raainxx]

No it's not backlight rail burn, it's EDP_INT_AUX_N burn, i check all PM_SLP_Sx it's all at 3,3V
my friend have the same mac, it work on external display.
i don't understand why you say "No dedicated GPU, so external video missing too"

 

[2informaticos]

Usually external video still present, when dedicated GPU available.
Very rare to have external in case like your.

EDP_INT_AUX_N is next to backlight high voltage output; that's the reason got burnt.

 

[raainxx]

ok i understand.
do you think the display is burn too?
thanks

 

[2informaticos]

Internal LCD should be good; if no broken...