[help] 820-01958 dead: 20v not switching

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  • phantomEVO
    Badcaps Veteran
    • Mar 2013
    • 488
    • USA

    #161
    yes 2 ohm...i'm going to give up.....why this motherf*ckers voltages are in loop?? and why are them stable if in dfu?

    Comment

    • phantomEVO
      Badcaps Veteran
      • Mar 2013
      • 488
      • USA

      #162
      so is it normal that i have not nand voltages?

      Comment

      • phantomEVO
        Badcaps Veteran
        • Mar 2013
        • 488
        • USA

        #163
        i understand, but i dont' want to give up....maybe i should open a new thread and write " i don't know the history of this devic: it switch to 20v but it seems in boot loop: what can i check"

        maybe restart from the beginning would be usefull...

        for example i think i MUST HAVE some power rails before to boot...is it possible that it does'nt boot because i miss some rails?!??!? is it possible that i miss for example ssd rails???

        i think i should start from:
        PPVCC_NAND_SSD0 (VCC for both nands)

        right?

        created by u9060...

        it is a little bit difficult for me to undertstand how u9060 works...i should have
        PPBUS_G3H_SSD0 to have it working right?​

        Comment

        • mon2
          Badcaps Legend
          • Dec 2019
          • 14030
          • Canada

          #164
          What is the resistance to ground of PPVCC_NAND_SSD0?

          If the resistance is low then the NAND is defective. Without a working NAND, you cannot complete the DFU. With a defective NAND with a low resistance, the power rail will not operate properly. Each SSD0 power rail needs to be inspected for the same conditions.

          Comment

          • phantomEVO
            Badcaps Veteran
            • Mar 2013
            • 488
            • USA

            #165
            PPBUS_G3H_SSD0 is 12,32
            pvcssd0_en is 0v
            pvcssd_avin is 12,32

            PPVCC_NAND_SSD0​ is 19k
            0,346 in diode mode

            Comment

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