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Macbook A1708 820-00840 stays on 5V and doesn't turn on 20V

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    Macbook A1708 820-00840 stays on 5V and doesn't turn on 20V

    Hi Everybody,
    I have three 820-00840 main with almost the same problem. They all are breezed at 5V state.
    There were other problems before i fixed them.
    So,
    First of all, I used PCD3215A10 instead of CD3215C00, which I have bought on Aliexpress.
    On the first board, I have mixed PCD3215A10 and CD3215C00.

    in spite of I checked everything according Mon2 article https://logi.wiki/index.php/CD3215_Bootup_Sequence (Thank you)


    First board has constantly pulsation between SMS and U3200 on the SMBUS_SMC_4_G3H_SCL and SMBUS_SMC_4_G3H_SDA lines. (Both lines Non-stop).

    Second and third have pulsation SMBUS_SMC_4_G3H_SDA only.
    But SMBUS_SMC_4_G3H_SCL rise and then pull down. Looks like somebody (SMC) puts this line to ground. Obviously without clock signal U3200 can't receive manage signal.

    Finally I broke my head and really need any help or advise.
    Thank you an advance.

    #2
    Sorry.
    I found out the error
    Insteadof SMBUS_SMC_4_G3H_SCL correctly is SMBUS_SMC_4_G3_SCL


    add:
    Only one of them, whichhas constantly pulsation between SMS and U3200 on the SMBUS_SMC_4_G3_SCL and SMBUS_SMC_4_G3_SDAhas a PP1V1_UPC_ XB_LDO_BMC 1.19V.
    But all of them have conversation between U2890 SPI.

    Comment


      #3
      The problem is solved.
      Only C0 series of CD3215 can be used.

      Comment

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