Samsung TV No Backlight Issue

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  • coolshrimp
    Senior Member
    • Nov 2016
    • 54
    • Canada

    #1

    Samsung TV No Backlight Issue

    Brand: Samsung 460UXN-3 LCD TV
    Model: LH46GWSLBC/ZA
    Size: 46" Inch

    I need some help fixing my TV i have here.

    When you power on the TV the backlight flashes on for 1-2 sec, each time you change inputs it will flash again for 1-2 seconds again.
    Then after about 30sec the tv will power off completely.

    So the power board all looks fine visually and I tested all the voltages on the connectors with a multimeter they are correct.
    I removed the Inverter board and the TV would stay on and not power off after a few seconds.
    With the inverter board removed the tv is working i can use a flashlight against the screen and see the picture.

    So i figured ok needs a new inverter board, i finaly recived a new one that i ordered online (SS1460_12C01), installed and the same thing.
    Tv no longer powers off after 30 sec, but still only flashes backlight for 1-2 seconds.

    so am i right to assume its the backlight bulbs themselves?
    is there a way i can test the bulbs?
    also can i simply disable the bad bulb once i figure out witch one?
    id rather not take apart the LCD and risk damaging it completely.
  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #2
    Re: Samsung TV No Backlight Issue

    First, you always look at the control signals and the supply Voltages first before doing any board changing.
    Since we do not have the TV in front of us to look at then you have ti supply us good clear pictures of the whole back side of the TV showing all the boards and then straight shot pictures of the boards that are clear enough for us to read the labels for each connectors on the boards.
    Never stop learning
    Basic LCD TV and Monitor troubleshooting guides.
    http://www.badcaps.net/forum/showthr...956#post305956

    Voltage Regulator (LDO) testing:
    http://www.badcaps.net/forum/showthr...999#post300999

    Inverter testing using old CFL:
    http://www.badcaps.net/forum/showthr...er+testing+cfl

    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
    http://s807.photobucket.com/user/budm/library/

    TV Factory reset codes listing:
    http://www.badcaps.net/forum/showthread.php?t=24809

    Comment

    • coolshrimp
      Senior Member
      • Nov 2016
      • 54
      • Canada

      #3
      Re: Samsung TV No Backlight Issue

      OK here are images.
      http://s102.photobucket.com/user/coo...20Samsung%20TV

      Like i said i tested all the voltages at the connectors coming out of the main power board and they read correctly as marked on the PCB.

      The Built In PC on the right is working.
      Inputs are working, as i can see image with flashlight as stated before.

      Comment

      • budm
        Badcaps Legend
        • Feb 2010
        • 40746
        • USA

        #4
        Re: Samsung TV No Backlight Issue

        "Like i said i tested all the voltages at the connectors coming out of the main power board and they read correctly as marked on the PCB."
        I see, so you are telling me that ALL the control signal are at correct Voltages and present?
        You see, the DCV for the power may be correct but how about the control signal Voltages? Read the basic TV troubleshooting guide so you will understand what the TV needs to function.
        Attached Files
        Last edited by budm; 11-01-2016, 09:21 PM.
        Never stop learning
        Basic LCD TV and Monitor troubleshooting guides.
        http://www.badcaps.net/forum/showthr...956#post305956

        Voltage Regulator (LDO) testing:
        http://www.badcaps.net/forum/showthr...999#post300999

        Inverter testing using old CFL:
        http://www.badcaps.net/forum/showthr...er+testing+cfl

        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
        http://s807.photobucket.com/user/budm/library/

        TV Factory reset codes listing:
        http://www.badcaps.net/forum/showthread.php?t=24809

        Comment

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