Hp dv4-5000 wsnu No Backlight

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  • karlox
    Senior Member
    • Dec 2017
    • 126
    • México
    #1

    Hp dv4-5000 wsnu No Backlight

    Good evening! I am working with a hp wsnu main boad rev motherboard. 2.1. Previously it did not turn on, replacing a 30v n channel mosfet according to a data sheet now it turns on But now the problem is that I do not have a backlight, in the lvds 1,2 connector it only activates 3v, I do not have the schematic and I have been guessing the connections .. Any help solving my problem .. Thanks..
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    • mon2
      Badcaps Legend
      • Dec 2019
      • 14022
      • Canada
      #2
      Re: Hp dv4-5000 wsnu No Backlight

      Post all markings on the logic board.

        Comment

        • karlox
          Senior Member
          • Dec 2017
          • 126
          • México
          #3
          Re: Hp dv4-5000 wsnu No Backlight

          Well, I attach full photos. Thanks
          Attached Files

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            • mon2
              Badcaps Legend
              • Dec 2019
              • 14022
              • Canada
              #4
              Re: Hp dv4-5000 wsnu No Backlight

              According to this webpage:

              https://www.laptopschematic.com/hp-p...agramdiscrete/

              see the reference to logic board # LA-4102P for the HP DV4.

              Based on this detail, see attached. It may match your LVDS connector pinout.

              Check the ground pins and see if there are bridged like the attached for your logic board. Then check the power rails, etc.

              Post your updates.
              Attached Files

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