Macbook A1989 / 820-00850 Restart problem

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  • GfilipeZ
    Member
    • May 2021
    • 43
    • Portugal
    #1

    Macbook A1989 / 820-00850 Restart problem

    Hi,

    I'm working on a A1989 820-00850 Logic Board.
    The customer complained that the machine restarted randomly.
    From the analysis I made to the Logic Board, I detected a small corrosion in the IC U7430.
    Although the diode values are all correct, I replaced the IC with another one. But the machine kept the same problem.
    However, I noticed that whenever I use the Heaven software, the machine restarts after a few seconds. That is, it is enough to have an increase in graphics processing for the machine to restart.

    Has anyone had a situation similar to this?
    Tags: None
    • skynet85
      Senior Member
      • Jul 2015
      • 124
      • Georgia
      #2
      Re: Macbook A1989 / 820-00850 Restart problem

      It is possible to start by inspecting the board for corrosion or(after) turning off the discrete card and test.

        Comment

        • GfilipeZ
          Member
          • May 2021
          • 43
          • Portugal
          #3
          Re: Macbook A1989 / 820-00850 Restart problem

          Thanks for your reply.

          Already looked for corrosion, and the only place i found was in the IC i mentioned above.
          This machine has integrated graphics, not a discrete card.

            Comment

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