This power supply is from my nephew.
This power supply was short-circuited, as soon as he connected the power cord, the electrical panel of the house would shut down.
I tested it in my house and it seemed to work well, the electrical panel of the house did not turn off. The mismatches of 5VSB, +12, -12, +5 +3.3 were all normal. I was not sure what the problem was ... until I got an electric shock from touching the metal case of the power supply.
It seems that there was a current drain to the earth.
My house is older and there are no grounded electricity outlets, which is why the electrical panel was not going down in my house.
I opened the power supply and found that the Class-Y capacitors had a small burn mark.
These capacitors are designated 103Z 1KV.
I tested both, one of them seems to be fine although it has less capacitance compared to a new one. 5237pF instead of 8222pF
The other was detected as a 2788 Ω resistor instead of a capacitor in my tester.
I changed both.
This is a measurement of a new 103Z 1KV capacitor
The power supply is now working properly. There is no more current drain to the earth.
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