A1278 820-3115-B PCB layers damaged?

[drscoot]

I've been working for while on this Macbook Pro LB.
On the bare board with power adapter plugged in, no green light. So far I noticed that there is no PPBUS_G3H. I removed F7040 and I measure 2,1Ohm on pin2 there. So I conclude there is a short. I went to voltage injection on that pin2: 2,2V is drawing 1,1A. I found the board is warming at C7553, c7555 and C7556, so I removed those, but still the board is drying the alcohol at that spot. There are no more components there!
Can it be that the trace in the layers of the PCB are damaged? It is an board with older water damage that I digged up again. I see a strange marking at the top side.
So does that mean the board becomes a 'donor board' or are there more things to try?
I have a google video, not sure if that is working like that? here

Also I noticed that the boardview and schematic I use for that B-revision board like I have 2 of, is also showing C7560 & C7530 in the (AXG) Phase section, but the 2 are not on my 2 boards (1 is working), as seen in the video. Not sure if I have the right BV and Schematic? Most parts are correct.

[piernov]

Re: A1278 820-3115-B PCB layers damaged?

Post high resolution pictures.
C7560 and C7530 are no stuff.

[drscoot]

Re: A1278 820-3115-B PCB layers damaged?

Here are some photos
Oh yes, I see it now too, it says Critical and No stuff at the same time.

[piernov]

Re: A1278 820-3115-B PCB layers damaged?

Layers are clearly burnt and shorting here. You need to dig up all the burnt material.

[drscoot]

Re: A1278 820-3115-B PCB layers damaged?

I'm not sure if this board is worth it, I have no experience with that kind of repair. You can find lots of video of board repairs, but layers repairs video's are not so common.
Do you know of an example repair like that?