LG 50PS30FD plasma, suspect YDRV boards

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  • vrajcevski
    New Member
    • Jan 2013
    • 2
    • Australia

    #1

    LG 50PS30FD plasma, suspect YDRV boards

    Hi,
    After going through the posts and searching, as well as getting the manulas from Scribd. I thin I need some specific assistance.

    The symptoms, On turn on, TVS starts, top half of screen has good picture and ottom has mal-discharge ( puprpleish) after af ew minutes TV goes black, sound is still onand remote owrks, ( can change channels etc).

    I suspect YDRV boards to be gone, but have no way to test them. Ina prior problem I had with the TV ( TV turning on and then immediately going to standby) I have replaced both YSUS and ZSUS boards with new ( from LG service) . The TV worked OK for almost 8 months, so this happened now.

    In the manuals and posts around, I found a fair amount on how to test the Buffer ( driver boards) but it is pretty tough to map since noe of them seem to come close to the ones I have. I have done the Diode test for each of the driver chips but there does not seem to be any particular issue I can pick up. would anybody have advice on testing the DRV boards or should I just pull the trigger and by the boards and see what happens? Would a DRV board somehow damage the Y sustain as well?
    I have seem quite afew threads with this kind of symptom, and they all seem to point to the YDRV but I'd like to take somewhat more informed approach . Board swapping can get me fairly close to half price for a new TV :-(.

    All help and advice appreciated....

    Vlad
  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #2
    Re: LG 50PS30FD plasma, suspect YDRV boards

    Going by the symptoms it does sound like a bad lower y-buffer.

    The newer y-buffers don't short to ground any more (well, not much at least) so there's no short test to make. Besides a maldischarged picture would not be a shorted buffer, just a damaged one.
    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

    • vrajcevski
      New Member
      • Jan 2013
      • 2
      • Australia

      #3
      Re: LG 50PS30FD plasma, suspect YDRV boards

      Just a quick update,

      replaced both top and Bottom buffer - but would appreciate if anybody has information on how to test them. I suspect it is realy the bottom one that is gone, but there does not seem to be an easy way to check/ test.

      Comment

      • tom66
        EVs Rule
        • Apr 2011
        • 32560
        • UK

        #4
        Re: LG 50PS30FD plasma, suspect YDRV boards

        I just recently made this.
        http://www.youtube.com/watch?v=51SZsfH60EY
        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

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