MacBook A1989 820-00850-A

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  • ZENDR
    New Member
    • Jan 2022
    • 4
    • Belgium
    #1

    MacBook A1989 820-00850-A

    Hi all,

    I've got a Macbook 2018 with touchbar that doesn't seem to be powering on. Doesn't have liquid damage or visible damage.
    - takes 20.2V and 0.4-0.5A
    - lcd doesnt appear to be turning on
    - no backlight, no keyboard light, no touchbar

    I got the schematic, and started to measure voltage on some components.
    Some clues where to start looking would be most welcome
    Any help is welcome
    Tags: None
    • mon2
      Badcaps Legend
      • Dec 2019
      • 14662
      • Canada
      #2
      Re: MacBook A1989 820-00850-A

      Measure and post the voltage of

      1) PPBUS_G3H.

      2) I2C lines.

      See attached.
      Attached Files

        Comment

        • ZENDR
          New Member
          • Jan 2022
          • 4
          • Belgium
          #3
          Re: MacBook A1989 820-00850-A

          Ppbus_g3h 12.6v
          i2c_pwr_scl 1.8v
          i2c_pwr_sda 1.8v

            Comment

            • ZENDR
              New Member
              • Jan 2022
              • 4
              • Belgium
              #4
              Re: MacBook A1989 820-00850-A

              Its fixed! It wasn't a hardware issue after all.
              I was able to get another Mac with usb-c and restore mine using DFU mode and Apple Configurator 2 on the working mac

              This guide is very helpful on how to enter DFU and how to restore:
              https://mrmacintosh.com/how-to-resto...into-dfu-mode/

                Comment

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