HP 4530s-no becklight signal

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  • LudonjaST
    New Member
    • Mar 2012
    • 5
    • Croatia

    #1

    HP 4530s-no becklight signal

    Hi to all!
    Have problem with led lcd beck light signal from motherboard after one of lcd chips burned and fried something on MB.
    Have schematic and I fixed burned spot but I'm afraid HM65 on MB is fried too.
    So I need advice how to override MB signal for beck light switch on?
    That should be done on lcd. What to do?
    Regards to all!
  • polytek
    Badcaps Veteran
    • Dec 2013
    • 496
    • TUNISIA

    #2
    Re: HP 4530s-no becklight signal

    check the lidsw signal is 3,3V present.
    Attached Files

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    • LudonjaST
      New Member
      • Mar 2012
      • 5
      • Croatia

      #3
      Re: HP 4530s-no becklight signal

      Originally posted by mabroukmedal
      check the lidsw signal is 3,3V present.
      Thank you for your effort and sorry for such late answer.
      I checked lid sw signal and it is present. There is 3.3v.
      I have that voltage on screen as well. That is what confuses me.
      Any additional idea?

      Comment

      • alas3376
        Badcaps Veteran
        • Nov 2011
        • 382
        • BENIN

        #4
        Re: HP 4530s-no becklight signal

        northbrigde issue

        Comment

        • LudonjaST
          New Member
          • Mar 2012
          • 5
          • Croatia

          #5
          Re: HP 4530s-no becklight signal

          I succeeded to do partial repair. Now I have light but can't regulate intensity of light. So bee it.
          I just installed 15K resistor between pin 7 and 8 on motherboard screen connector.
          Maybe my case help somebody else in future.

          Comment

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