LG 42LD450 no picture&sound problem

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  • spyrex
    New Member
    • Aug 2013
    • 4
    • TURKEY
    #1

    LG 42LD450 no picture&sound problem

    Hi,
    I have 42ld450 Lcd TV. Picture and sound goes off when watching. I powered off and on but red light blinling continuously without backlight, picture, sound.

    I checked voltages from PSU and there is no problem about voltages.

    There is a switch on logic board and when press it backlights turn on for a second and goes off. I think backlights working well.

    Do you have any idea?
    Tags: None
    • spyrex
      New Member
      • Aug 2013
      • 4
      • TURKEY
      #2
      Re: LG 42LD450 no picture&sound problem

      I replaced all capacitors on powerboard but nothing changed.

      Powerboard voltage outputs like this;
      Left side values printed on pcb, right side values measured.
      3,5V - 3,3V
      12V - 12V
      20V - 21V

      I noticed that when turn on tv and measure voltage from logicboard to T-con, multimeter shows 0V.

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