820-00840 - Liquid damaged - Works when lid open from sleep, no backlight

[nelo1012]

820-00840

since i believe there is no board view and schematics, i am using 820-00875

This board was liquid damaged, repaired all obvious damage, and computer works fine until i close the lid, it wakes up but has no backligh
i can see the image in the background,

any ideas where should i start?

 

[nelo1012]

Hello guys, I’m still stuck on this one. Any suggestion helps, thanks

 

[bjf]

I’m guessing lid/hall sensor

 

[nelo1012]

The backlight doesn’t come back after the MacBook is set to sleep by closing the lid but it does come back fine if it’s set to sleep from within. Please see attached video of the issue.

 

[JohnB8812]

Sounds like corrosion on the lid sensor like bjf said. Inspect it for corrosion

 

[nelo1012]

There was no corrosion at all in this area,

and looked again, no corrosion, should I still replace just to make sure is good?

 

[2informaticos]

Why don't you measure SMC_LID signal?
See if you get correct value and stable after lid is open.

 

[bjf]

Check SMC_LID and check everything around U5255. I'm betting one of those resistors is blown or you have a continuity issue there.

 

[mainmacman]

any update here?

 

[nelo1012]

replaced the customers board, at the end the board would flash for a split second then go away,