820-00138 PP3V3_SUS shorted to ground


Board takes around 88-94 mah, and stays.

No liquid damage signs but it looks like its been ultrasoniced before.

Ive seen boards with no spi rom act sort of this way, so I measured U6100. Noticed immediately PP3v3_sus was shorted to ground and 0v, though nothing was getting warm, pch was normal, and 3v3_sus coming out and to of the pch was present, and 3v3_sus at u8130 was present as well.

My question is how should I go about fixing this? run a wire from u8130? where does 3v3_sus come from, to u6100?

by the way u6100 is removed and pin 8 is still shorted on the board.


Staff member
"u6100 is removed and pin 8 is still shorted on the board"
Why would you run an wire from 3V3_SUS to ground?
Eliminate the short first.
Use voltage injection method; start with 1V, no more than 4V.
my fault, by run a wire I mean destroy the pad and then run a wire to pin 8.

injection of 3.3v to that pin skyrockets it to more than 4 amps.

1.0v takes it to over 3 amps. however pch doesnt get hot.

edit: Im struggling to find anything getting hot when injecting voltage.
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Staff member
Set amp limit of the PSU to max; be sure doesn't get into protection mode.

3V3_SUS rail is extended on the board and may have other points shorted to ground.
max my psu is taking is 1.38v at 4.5 amps.

I injected it on for a straight minute, 5 times, grabbed all parts, and touched all parts of the board, and not one hot spot.

The things that get hot are my injection probes, thats it.

Could this be a broken trace?. Like a leakage to ground?


Staff member
Is possible to be short between copper layers.
But you should get a better PSU.
At 2V you may get 8-9A which will heat something for sure.
I recommend many times to get 20A PSU for voltage injection.
Also use ticker cables.
Scratched pin 8 down to just board, then filled with coating, but not over the small hole I made. Pin 8 was fully free, not connected to ground, or anything, then I soldered a wire from pin 5 of U8130 to pin 8 of u6100, and yay we now get 3.3v on the spi chip. However still same 94 mah.

Will be uploading voltages shortly

realized pin 7 has a trace connecting to it, and it might have been smarter to just leach off of that but anyway
3v3 sus is present everywhere, as well as pm_slp_s4, s3, and 5v_s0. I narrowed it down to u7600, pin 13 is 0V, whole circuit looked fishy so I replaced almost all resistors and capacitors, and u7600. However still same issue. I noticed pin 13 was 0v but r7601 was 5v. Checked continuity and there is none. Going to run a wire now
this board seems like it was bent or dropped or something before, so many broken traces, most non important tho, these are only two known critical.
ran wire to pin 13, now u7600 gets really hot and shorts to ground. Pin 13 is shorted, as well as 14. I see the line is connected to P1V05S0_AGND, is this supposed to happen or is u7600 just bad?
Im going to end this post, as now im noticing all_sys_pwrgd is shorted, pin 1 of u1950 is not connected to all_sys_pwrgd, which it should be, its not going to ground either so, too many broken traces, wouldnt sell this to anyone even if fixed, Ive found 10 broken traces already. Thank you 2informaticos for your help!