820-3115 PP3V42_G3H short or no?

[bighead]

Hi,

I've a liquid damaged 820-3115.
The liquid damage was around SMC and PP3V42_G3H.

I had to change the SMC, because there was no green light.
After I replaced the SMC this macbook was working fine.
However after few hours it turned off and the green light went off.

There was a short on PP3V42_G3H (40 ohm short).
I hooked up my PSU give it 1V and 1A. It drew 0.8A and nicely went down to 0A in 10sec or less.
So of course I couldn't find the shorted component. It's not like something blown.... the short just was gone.

Well, after an hour the problem is back. The macbook turns off and on. It starts booting and turns off and on.
Sometimes as soon as the white screen comes on sometimes after it booted. It does the some thing on my desk without anything attached.
I tried different DC-IN board.

I have a low resistance on PP3V42_G3H. It's now 400 Ohm. What could this be? I guess it's a leaking cap just the question is how the hell I'm gonna find it?

Thanks.

 

[larossmann]

Under that foam thingie near the audio circuit are two caps that always die,I think C6403 & C6405. Remove them. You can't see them smoke when you run voltage through them because they're hiding under the foam.