LG 50PA6500 No Picture

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  • orangewindhoek
    bluehawaii
    • Jun 2018
    • 4
    • Australia

    #1

    LG 50PA6500 No Picture

    Hey guys. I have an LG 50PA6500 TV with no picture. TV automatically cycles to/from standby when powered; indicated by red light which clicks on/off. There is a buzzing sound coming from y-sus when light is on. When Y-sus was disconnected, the red light stayed on (i.e. cycling stopped). I have read all posts on badcaps regarding this model. As per sticker (see attachment), ideal voltages are:

    Vs = 205 V
    VZB = 150 V
    VSC = 150 V
    Va = 55 V
    -VY = -190 V

    When both buffers were removed and y-sus connected, buzzing continued and the voltages were:

    Vs = 206.0 V
    VZB = 149.7 V
    VSC = 151.3 V
    Va = 54.5 V
    -VY = 191.0 V

    When top buffer was isolated and y-sus connected, cycling continued on/off with no picture; similarly with bottom buffer. Buffers were tested for continuity and no shorts were found on either.

    Is a tear possible without any shorts on either buffer? If so, is the only conclusion a tear in both ribbons?
    Attached Files
  • Andrew F. Ali
    Badcaps Legend
    • Jan 2014
    • 2450
    • Trinidad & Tobago

    #2
    Re: LG 50PA6500 No Picture

    Look at the CTRL Bd and search for 2 pins/holes labeled AUTO-GEN. Disconnect the Main Bd. from the CTRL Bd. Solder/connect a jumper between the AUTO-GEN pins/holes. Apply the ac and if the Panel is good the Test Patterns should show. If the screen shows a perfect White display, then the Panel is OK and your Main Bd. or LVDS cables is the fault.

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