[Mr.Dutch]

Originally Posted by CptKirk I used an OHM meter and found short circuit (0 ohm) to GND (VSS point or GND around the motherboard). When i look with a magnifier (X20), i don't see anything

dous your meter has range settings?, if so set it to the lowest (for example 0-200ohms)

[CptKirk]

I used the lowest range (0-200) and found 00.6 (virtually 0).

[underwurlde]

Did you do continuity test on a powered board, or on a board that had been recently powered. Voltage (or any residual voltage) present on the board when doing such a test will confuse the meter.

But I'm guessing that this is not the case and you do have a shorted supply on your PS3 motherboard. Finding such shorts can be a real head-scratch. But you have an advantage: you have done something to the PCB and then un-did that something, so it is that something that has caused the short, so obviously look at any work you've done.

Also fried chips can short the supply too and the source of your problem could be the flash devices.

Other than that, trying to describe how to fault find such problems via a forum is a problem in itself!

Good luck,

Andy

[Mr.Dutch]

Originally Posted by CptKirk I used the lowest range (0-200) and found 00.6 (virtually 0).

there's at least a 390ohm resistor between that 3,3V and ground, and there are several capacitors that could have influence on the reading..

i suggest to set the meter to voltage and measure that point when the ps3 is on to see if there's any output...

i can eventually look up measure points in the schematic for the sem board, i think this one is closest to your board,

[CptKirk]

Thank you all!!
I found the short
A very tiny drop of solder fell on a cap
Now i have 390 ohm between VCC point and GND.
I'm so happy.
I can now reassemble the parts and test it.

[Mr.Dutch]

Originally Posted by CptKirk I can now reassemble the parts and test it.

fingers crossed, if you are not getting power then you probably damaged the Q6004 part of the fuse in the first part of the chain.

[underwurlde]

^ I think that may be a self resetting poly-fuse. Certainly looks like one.

Yep, fingers crossed.

Andy

[CptKirk]

I'm not electronician, i've just a little skill of solder and i don't understand what is Q6004.
But, you're right: green and immediately 3 beeps and red. Sadness.
I've an old YLOD CECHG04 with SEM-001 board. Maybe can i use it to change this Q6004 ?
Is it the Q6004 near the VCC point?

[Mr.Dutch]

Originally Posted by CptKirk I've an old YLOD CECHG04 with SEM-001 board. Maybe can i use it to change this Q6004 ? Is it the Q6004 near the VCC point?

if you are skilled enough you could try to swap it out, but be carefull, static electricity or too much heat would kill it.

if you are able to measure voltage you could try to measure the point i added to your board, it's just before the Q6004 part, if that one dousnt come to life then the problem is earlier and not in Q6004.



SEM

[CptKirk]

So, I measured the VCC point and the four 3V3 points you told me. When I turn on the console, the 3.3v never comes