hp g56 no backlight

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  • woodford
    Member
    • Jun 2011
    • 27
    #1

    hp g56 no backlight

    i have seen a few g56 laptops with the problem of no backlight.they all have led screens so no inverter to diagnose and i cant seem to find any fuses on the mainboard, any idea's where to start diagnosing this fault, ive tried new cable and new screen so definately mainboard issue and ive seen enough of this problem to think it may be a common fault.

    thanks
    Tags: None
    • thesloc
      Banned
      • Dec 2011
      • 587
      #2
      Re: hp g56 no backlight

      there you go, the problem is most likely in the lcd..

        Comment

        • Mario
          Senior Member
          • Sep 2007
          • 64
          #3
          Re: hp g56 no backlight

          Theres two types of LED lcd's, both40 pin connector, if it has a smaller one, the backlight driver is on the mainboard. Maybe check there if the output has any voltage. It should be 30 or 27 v. The longer connections have the backlight controller on the LCD. Check if theres 12v going in to the LCD connector. And check the BL_EN there should be 5v or 3.3 v. Maybe you can force it on with like a 3v or 5v power source.

            Comment

            • b700029
              Banned
              • Sep 2010
              • 640
              #4
              Re: hp g56 no backlight

              If you are certain what the connections are, and the current requirements, you can try powering up the LEDs directly.

                Comment

                • unlockdev
                  Senior Member
                  • Apr 2011
                  • 81
                  #5
                  Re: hp g56 no backlight

                  common problem
                  Filed +3.3 to plug a 36 foot light running at maximum and not adjustable.

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