LG 39ln575s - power ON, backlight ON but no screen

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  • bajdik
    Senior Member
    • Aug 2015
    • 64
    • Czech Republic
    #1

    LG 39ln575s - power ON, backlight ON but no screen

    LG 39ln575s - power ON, backlight ON but no screen.
    I checked TCon board V390HJ1-CE1 and VCL -8V, VCH 30.2V.
    Display is HC390DUN. With both strip is backlight only - nothing on the screen.
    If I put 1st strip off, I see 50% black 50% white. If I put 2nd strip off, see some lines vertical/horizontal with pink color (probably color of LG logo) and after that, white on thle left corner.

    The IC chip CM501 (probably booster for VCL and VCH is hot - after 1 minute is not possible to put finger for more than half second.. So I think it has got about 70C. Is it normal?

    Has anyone voltage for test pins on the TCon board?
    Any idea? Thank you.

    Last edited by bajdik; 12-11-2023, 11:20 AM.
    Tags: None
    • lotas
      Badcaps Legend
      • Jan 2016
      • 4589
      • Russia
      #2
      No, this is not normal, either there is a short circuit at the outputs of this chip, or the chip itself is not fixed.

        Comment

        • bajdik
          Senior Member
          • Aug 2015
          • 64
          • Czech Republic
          #3
          OK, I will buy a new T-Con board and try it.

            Comment

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