LG 50PJ350 bad buffer ?

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  • diif
    Badcaps Legend
    • Feb 2014
    • 6978
    • England

    #1

    LG 50PJ350 bad buffer ?

    My friend has a 50PJ350 that would turn straight off after power on.
    YSUS and ZSUS had shorted components and they were replaced.
    The TV now powers on, some white speckles appear from the bottom then the TV clicks off.
    Is this an indicator of a bad buffer ? or is there something else on the YSUS/ZSUS that we've missed ?
    Attached Files
  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #2
    Re: LG 50PJ350 bad buffer ?

    More likely Z.
    You can see if a buffer is shorted by checking across VSCN and VFG or sometime across the VSCN resistor.
    It should be in the 100's of kohms.
    If VSCN is present (~150V) then you do not have a shorted buffer.
    Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
    For service manual, schematic, boardview (board view), datasheet, cad - use our search.

    Comment

    • diif
      Badcaps Legend
      • Feb 2014
      • 6978
      • England

      #3
      Re: LG 50PJ350 bad buffer ?

      Thanks Tom, I've not had much dealings with plasma TVs. I'll go over to my friend's house later and check for VSCN.

      Comment

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