iMAC 27" with PSU PA-2311-02A - not giving voltages

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  • ktmmotocross
    Boardkiller
    • Feb 2014
    • 3578
    • slovakia
    #1

    iMAC 27" with PSU PA-2311-02A - not giving voltages

    Hello.
    Have this 27" iMac, that suddently after 2/3 yearsin storage wont start. when i connect power i was hearing some electric sparks sound from back of PSU. i wigle whole mac and it start with chore. so i remove PSU to check, but there is only AC input and output to board and see no bad connections. i resoldered big chips but nothing changed.
    when i measure it outside i found that only 1.3V on SDA/SCL pins. no PS_ON voltage or other voltages

    what can i measure to have better understanding where is problem?

    anybody know what voltages should be active when connected to power?

    i think that SCL/SDA should have 3.3V and PS_ON should have 3.3V and PP12V_G3H_ACDC should be 12V
    Attached Files
    Last edited by ktmmotocross; 08-18-2023, 10:44 AM.
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