Search schematic for +PWR_SRC and open respective jumpers, the measure resistance as you go. Injecting voltage is not recommended since we don't know where the fault is and would thus need to keep voltage low, which means current will also be low and nothing will get hot.
Try removing PU603 also although it should not make any difference since PL602 has been removed. Make sure the pad for PU602 is clear of any soot by the way.
Practice on a donor board if needed. Removing components and testing is safer than injecting voltage. I'ld also remove PL603 and PL604 to isolate +VCC_CORE and check for short again. It also decreases the risk of accidentally sending unsafe voltage to the CPU.
In any case, I strongly suggest you tune in you soldering skills on donor boards if you do not feel very confident yet.
Practice on a donor board if needed. Removing components and testing is safer than injecting voltage. I'ld also remove PL603 and PL604 to isolate +VCC_CORE and check for short again. It also decreases the risk of accidentally sending unsafe voltage to the CPU.
In any case, I strongly suggest you tune in you soldering skills on donor boards if you do not feel very confident yet.
Hello!
I removed the PU603 but the shortcircuit was still there.
I appied 1w from bench psu and while i was searching for shorts the short gone, now Vin to Ground is 40MΩ
The short in Vswh remains though.
What do you think?
What voltage did you apply when finding the short and where did you apply it? You most likely burnt out the short .
What is the resistance value of VSWH?
VSWH goes to +VCC_CORE which is CPU core voltage and therefore having a low resistance is normal.
If you remove PL603 and PL604, you should only read low resistance on pin 1 and 2. Pin 3 and 4 should read open circuit.
Ι applied 1v 1A & 2v 1A, not sure when the short burnt, i noticed it right after 2v 1a.
Vswh resistance to ground is 3.5Ω
Just removed both PL. I'll sent measurements in a few mins
Where were those measurements taken? PU602/PU603? What do you mean by 'before SMD'?
Pin 1 and 2 does not look good. Pin 2 (assuming you meant VCIN of PU602/603) is indicating a short on +5V_RUN and pin 1 (ZCD_EN#) could be due to a faulty PU601. Try removing PU601 and measure again.
If you remove PL603 and PL604, you should only read low resistance on pin 1 and 2. Pin 3 and 4 should read open circuit.
I was referring to pin 1,2,3 and 4 of PL603/604 by the way.
Where were those measurements taken? PU602/PU603? What do you mean by 'before SMD'?
Pin 1 and 2 does not look good. Pin 2 (assuming you meant VCIN of PU602/603) is indicating a short on +5V_RUN and pin 1 (ZCD_EN#) could be due to a faulty PU601. Try removing PU601 and measure again.
I was referring to pin 1,2,3 and 4 of PL603/604 by the way.
measurements taken on PU602, one probe on the side towards MB (not side towards burnt PU602) and the other on GND.
For some strange reason i can't find PU601 (please check attachment)
PL603 and PL604 have only 2 pins.
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