820 3676, No bklt ,no liquid damage

[Noguinfor]

Hey,

No backlight,

EDP_BKLT_PSR_EN 3.3V and the gate off of Q7700 is not being pulled low. I've replaced U7700 and Q7700 still doesn't work.. IDEAS??

ty

 

[dukefawks]

Is there even an image? Known good LCD for 2013 model? SMC_LID high? PRAM reset?

 

[Noguinfor]

yes i can see a logo Apple and in external monitor work's too.. unfortunately i don't have a LCD for 2013, in the moment only have LCD for board 820 3462..

SMC_LID - 3.3V and i already do a PRAM reset!

Duke a quick question, LCD compatible for 820-4924?? only works with 2015 LCD?? thank you

 

[dukefawks]

No 2015 is different!

A1425 LCD will work for testing.

 

[Noguinfor]

same think apple logo but no bklt. pin 3&4 = 0.473v with flat cable connect and 0.175v without flat cable.

 

[dukefawks]

pin 3 and 4 on the LCD connector should be pulled up to 5V. Probably corroded traces.

 

[Noguinfor]

Pin 3 = 4.8V and pin 4 = 5.1V.. not easy to find this problem.. i need to wait for a good screen to exclude that..