820-00239-09 No boot

[DaveDD]

Hi all!
Came in this 820-00239-09. No signs of corrosion, MB looks perfect.
Customer report that the machine works perfect yesterday evening, but this morning macbook won't turn on.
CPU Vcore steady at 1.07v measured on L7210/L7220 so no boot I guess.

with another bin came from this forum (filename "A1706 820-00239-09 - clean.bin") , Vcore stays at 0v.
Where should I start?
Thank you

 

[2informaticos]

You can find more dumps on badcaps forum; try one and comment.

 

[DaveDD]

tried 5 or 6 different bin files.
I get 0v with most of them and a weird 0.85v.
The last one that i tried led me to the same point: steady 1.08v
I'm working with board alone on my desk.

 

[2informaticos]

Then probably bad CPU.

PLT_RESET_L comes high?

 

[DaveDD]

PLT_RST_L comes high after a few seconds and stay high at 3.33v stable

 

[DaveDD]

So nothing that I can do?

 

[2informaticos]

If PLT_RST_L comes high power on sequence is completed and remains a problem related with data communication between the chips.
Just in case, check all resistors from LPC bus, R1320-7.
Also check all SPI Bus Series Termination resistors and their traces.
You can try to heat CPU with quality flux; in case of accumulated crap underneath.