No backlight. How to check Inverter card

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  • IamPritesh
    Badcaps Veteran
    • Aug 2017
    • 354
    • India
    #1

    No backlight. How to check Inverter card

    I have this compaq preasario v3000 . It now starts fine..I can see picture if I use flashlight.. and on external monitor .


    I suspect it could be a case of either bad invertor or ccfl. How do I check this ? I do not have any spare invertor to swap and test....

    p.S -- Togling the lid switch enables backlight for a second and then it goes back to black screen
    Tags: None
    • ktmmotocross
      Boardkiller
      • Feb 2014
      • 3553
      • slovakia
      #2
      Re: No backlight. How to check Inverter card

      what about checking backlight enable signal?

        Comment

        • IamPritesh
          Badcaps Veteran
          • Aug 2017
          • 354
          • India
          #3
          Re: No backlight. How to check Inverter card

          Originally posted by ktmmotocross
          what about checking backlight enable signal?
          where could I find this signal ? LVDS connector ? I dont have the schematics

            Comment

            • mmartell
              Badcaps Legend
              • Oct 2013
              • 3189
              • Canada
              #4
              Re: No backlight. How to check Inverter card

              Pictures, pictures, pictures where are the pictures ?

                Comment

                • piernov
                  Super Moderator
                  • Jan 2016
                  • 4435
                  • France
                  #5
                  Re: No backlight. How to check Inverter card

                  Usually bad CCFL. Connect any other laptop CCFL to confirm. (connect backlight connector from another laptop panel)
                  OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

                    Comment

                    • ktmmotocross
                      Boardkiller
                      • Feb 2014
                      • 3553
                      • slovakia
                      #6
                      Re: No backlight. How to check Inverter card

                      https://cdn.badcaps-static.com/pdfs/...4c839989cb.pdf

                      check BRIGHTNESS_CONN
                      Last edited by ktmmotocross; 05-17-2019, 10:34 PM.

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