Macbook Pro 820-00840-A 20V but not turning on

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  • TVMexicana
    Member
    • Mar 2019
    • 32
    • USA

    #1

    Macbook Pro 820-00840-A 20V but not turning on

    Hello all,

    I'm trying to figure out the issue with this macbook pro. It will not turn on or charge. When I plug in the charger using my USB-C ammeter I can see the voltage go from 5V to 11.7V to 20V but there is no current consumption. PP3V3_G3H is present. PPBUS_G3H attempts to go on but goes back off after only a very brief second. I do not see any short on PPBUS_G3H nor do I see any other obvious shorts on the other power rails that come after it. I removed U7650 to isolate all power rails that are created from it and I still get the same symptom. I also tried to replace U7000 with no change.

    I would greatly appreciate any input you have to offer. I have also attached the schematic and board view below.

    Thank you!
    Attached Files
  • piernov
    Super Moderator
    • Jan 2016
    • 4435
    • France

    #2
    Re: Macbook Pro 820-00840-A 20V but not turning on

    History?
    If you remove F7000 do you still get 0V on its pin 1?
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

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    • TVMexicana
      Member
      • Mar 2019
      • 32
      • USA

      #3
      Re: Macbook Pro 820-00840-A 20V but not turning on

      Hello, thank you.

      My symptom actually ended up changing. It may have ended up happening after changing U7000, I can't remember if I measured PPBUS_G3H after replacing this IC or if I only checked with the ammeter for activity after replacement. Either way I now have a steady 13V on PPBUS_G3H and the current consumption on the ammeter goes between 0mA and 10mA. Still no power though and I do not measure activity on any other voltage rail.

      As for history, I don't know much. There is no sign of liquid damage, the motherboard looks squeaky clean.

      Comment

      • alberto232732
        New Member
        • Oct 2020
        • 5
        • mexico

        #4
        Re: Macbook Pro 820-00840-A 20V but not turning on

        gracias colega fue de gran ayuda

        Comment

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