LG 47LN577V backlight turns off

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  • PowerAmpFreak
    Badcaps Veteran
    • Feb 2010
    • 982
    • Sweden
    #1

    LG 47LN577V backlight turns off

    This LED-TV, LG model 47LN577V turns on backlight and shows logo but within one second turns it off again.
    The backlight control signals are OK from mainboard, also the dimming control is OK.
    So this happens internal the PSU/Led driver board.

    Since the board is quite cheap I bought a new one, but exactly the same problem is still there.
    So, I guess this all relates to crappy led strips giving either too high or two low current for the led control to be happy?

    I will try to power up the led strips by an external powersupply and see if it looks normal.
    Tags: None
    • zomi
      Badcaps Veteran
      • Nov 2011
      • 509
      #2
      Re: LG 47LN577V backlight turns off

      Classic bad backlight..
      You will have a bad led or 2 somewhere

      happy hunting

        Comment

        • PowerAmpFreak
          Badcaps Veteran
          • Feb 2010
          • 982
          • Sweden
          #3
          Re: LG 47LN577V backlight turns off

          IMO today's LED-TV's are crap. Long live the plasma technology even if it was bulky and expensive to produce.
          But it last long.

            Comment

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