Apple MacBook Pro / Model A1990 / 820-01041-A / 5v .03a /

[zeydullak]

Hello,

We have an Apple MacBook with a 820-01041-A board, it uses 5v and .03a. the board has water damage on C9081 and the testing pads between C9081 and J4801.

What should we start with looking at first?

 

[2informaticos]

Check diode mode to ground at PPBUS_G3H and corresponding SSD power rails.

 

[zeydullak]

Diode mode to ground on PPBUS_G3H_SSD0_SNS is .0107.

 

[2informaticos]

0.010 is almost short.
Remove C9081 and U9080; test again diode mode readings on mentioned lines.

I hope you've already removed the corrosion...

 

[zeydullak]

0.010 is almost short.
Remove C9081 and U9080; test again diode mode readings on mentioned lines.

I hope you've already removed the corrosion...

Yes we have removed the corrosion, after removing U9080 and C9081 the readings are now 3.543.

 

[2informaticos]

3.543 in diode mode with red probe on ground???

I asked about PPBUS_G3H and also SSD power rails.

 

[zeydullak]

yes that is correct, that is the reading we got on PPBUS_G3H_SSD0_SNS.

 

[2informaticos]

Is the same PPBUS_G3H, where you should get 0.500 aprox.

You still don't want to post SSD readings; there are various small coils, but easy to access.