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Macbook pro A11989 820-00850 SSD not detected after issue with power 5V instead of 20

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    Macbook pro A11989 820-00850 SSD not detected after issue with power 5V instead of 20

    Hello
    I have a issue with a 820-00850 the mainboard was not going to 20V it stays on 5V - 0.06A . I have checked different voltages and they seems to be ok.
    So i have used Apple Configurator 2.6 from another Macbook to program the T2 Firmware. (Seen on a Louis Rossman Youtube)
    After this has been done the macbook is starting again so this was causing the problem but it is not starting there is the Question Mark folder on the display.
    I have tried to start with Command + R and there reinstall the operating system from Internet but when the download was complete and de install started there where no drives to install. So i think the SSD is not working ?
    Checked the voltages around the ssd SSD PP2V7NAND_SSD = 2,5V -PP1V8_SSD0=1.8V - PP0V9_SSD0=0,9V - PP3V3_S5= 3.3V
    What i dont understand is when the firmware got corrupted can this lead to hardware issue ? Maybe i am complelty wrong and is it now a software issue so that the disk is working but not showing.

    What i also noticed also that the power on/off button was not working when i pressed on it (maybe that there was a bad connection when i temperarly mounted the board in the case).
    I had the idea to go again in the DFU mode (before i done the firmware flash it was automatic in this mode) and try again and see what there is maybe wrong.

    I dont know where to search anymore i am not familiar with apple more Pc..
    Anyone with a suggestion ?
    Thx

    #2
    Re: Macbook pro A11989 820-00850 SSD not detected after issue with power 5V instead o

    Remove all power. Meter in DIODE mode.

    Red meter probe, yes RED to ground.

    Black meter probe to point to test.

    Check diode mode to ground on the LDO rails of all CD3215 chips.

    Post each measurement.

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