820-2877 turns off because of backlight circuit

[max]

hi, this is my first post at the forum, i really appreciate what you are doing here guys it helped me a lot so thank you
this board is for 2010 MacBook it was working fine until the screen went black as the customer said.
i checked the backlight circuit and concluded that when i disconnect the fuse the machine boots fine but with no internal screen external works fine though. replaced most of the components but still the same turning of exactly when it tries to get to the white screen or when the backlight tries to turn on.
replaced these components:
U9700
D9710
Q9807
LVDS connector
no short to ground and the resistance to ground on pins are OL on all pins except the ground pins
have no idea what to do next
any help is appreciated
thank you
note: when i inject 12.5 volt on pin 2 of R9700 PPVIN_BKL
the u9700 gets hot and burned pin 3 and 4 removed and replaced with a good chip still the same and no short to ground on the chip pins until power is injected.

 

[2informaticos]

Check R9715/16 then replace U9700.
Be sure D9710 is not shorted A-K.
Also check continuity between U9700 pins and external components.
R9730 is OK?

 

[max]

thank you for the replay,
R9715 is 1M and6 R9716 is 244k
continuity is good no short to ground on D9710
R9730 is 11 ohm

 

[2informaticos]

I asked for short A-K on D9710.
Check if ground points of U9700 really have contact with MLB ground.
Double check traces and solders on U9700 area.
Finally try a new chip, but do not inject voltage again.