Hello everyone,

I've faced a problem that my iMac does not start anymore. After a short investigation, I've found that PSU does not work and does not produce any stand-by voltage.

With a DMM I've found a short on 24V line and the problem was in Schottky diode D200. Another issue that I've found is a broken n-FET on a 12V line. After removing these components the short has disappeared. I replaced the diode witр a 30CTQ060 and transistor with another n-FET (I did not have exactly the same transistor). Now PPS works fine without load on the output.
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Re: iMac 24 PSU LITEON PA-3241-02A1 250W

Hello maki,
These are shunt resistors with a nominal 0.012 0.040 Ohm respectively