820-2850 backlight turns off halfway through start up

nate8organic

New member
Got in a 2850 board that powers on fine back light is good and about halfway through the start up the screens backlight turns off, i think its about where the system is starting to load into the menu and the screen normally blanks for a second and then boot in, but this one just turns off the back light, i have data on the screen with a flashlight. i have not done any testing yet, wanted to see if anyone has seen this before and what might be causing it? i did replace c9560 from the start.
 

nate8organic

New member
Okay after a little testing, i noticed if i don't touch the macbook as it boots up the backlight will not turn off, but if i bump the macbook or touch t4001 or anywhere on the board the backlight turns off. After the backlight turns off i get 0v on both BKL_PWM and BKLT_EN. if i tap the board some more it will not turn back on.
 
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