820-02098 stuck at 5volts and cycling at 0,000 amp - 0,030 amp

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  • meineiid
    New Member
    • Jan 2019
    • 9
    • Germany
    #1

    820-02098 stuck at 5volts and cycling at 0,000 amp - 0,030 amp

    Hi i got an A2442 with liquid damage. The Board is stuck at 5volts and cycling at 0,000 amp - 0,030 amp. Its not in dfu or recovery, i also tried to set it in dfu but doesnt work. With the old Macbooks I could always go through the power sequence, but with the new ones I don't know. I measured these rails PPBUS_AON= 12,35v PP3V8_AON= 3,8v PP1V8_AON= 1,8v PP5V_S2_MAIN= 0v . In logi wiki i says that "most important power rails now are pbus, 3v8 and 5v_S2" but i dont think its the PP5V_S2_MAIN i think something before that.
    Can someone help?
    Tags: None
    • mon2
      Badcaps Legend
      • Dec 2019
      • 14126
      • Canada
      #2
      Being USB Type C powered, start with a good review of the CD321x ACE power delivery controller. Each and every such controller must be functional to allow for the 20V power delivery contract to be selected to power this logic board.

      Review the LDO rails of the CD321x ACE controllers. You can use the following as an excellent guide:

      https://logi.wiki/index.php/CD3215_Bootup_Sequence


      Be sure to watch this video (if not done already):

      https://www.youtube.com/watch?v=CAGnMR1aVuE

      Louis Rossmann has another on the same topic.

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