LG Plasma TV power supply output double the rated voltage.

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  • PCcruncher
    New Member
    • Dec 2016
    • 6
    • USA

    #1

    LG Plasma TV power supply output double the rated voltage.

    Hi, I have a LG Plasma TV model 60PA6550 that will not show a picture.
    The TV will click on from standby, and I have sound. The remote works for power, and volume/mute functions.
    I have tried unplugging the y-sus and z-sus boards separately and together, but it doesn't change anything.

    I have inspected the boards, and do not see any bulged Caps (I was hoping this would be a simple fix) The fuses are good as well.


    When I test the power output, it is approximately double the rated voltage


    For example, The pin for m5v actual output is 10v, the VA is supposed to be 55V but is 120v, and the VS voltages are 457v instead of 201-206 as stated on the board.

    Also, when the power supply is on, the red capacitor (img_3064) is making a steady ticking noise.


    My question is, Can I fix these problems either by repairing the components on the power board, or replacing it altogether? Or will the high voltages have damaged the video boards, and it won't be worth repairing any of it?

    Any thoughts, questions or troubleshooting tips are appreciated!
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  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #2
    Re: LG Plasma TV power supply output double the rated voltage.

    Are you sure your meter is good?
    Batteries for the meter is good?
    Set to DCV mode?
    Correct GND being used?
    If you truly have double Voltages, lots of parts will be damaged.
    Never stop learning
    Basic LCD TV and Monitor troubleshooting guides.
    http://www.badcaps.net/forum/showthr...956#post305956

    Voltage Regulator (LDO) testing:
    http://www.badcaps.net/forum/showthr...999#post300999

    Inverter testing using old CFL:
    http://www.badcaps.net/forum/showthr...er+testing+cfl

    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
    http://s807.photobucket.com/user/budm/library/

    TV Factory reset codes listing:
    http://www.badcaps.net/forum/showthread.php?t=24809

    Comment

    • PCcruncher
      New Member
      • Dec 2016
      • 6
      • USA

      #3
      Re: LG Plasma TV power supply output double the rated voltage.

      Budm, thanks for your reply.
      I feel like an idiot, I assumed the higher voltages to be AC, with the meter switched to the correct DCV setting, the power supply does indeed have the correct voltages.

      So this leaves the troubleshooting to likely be the y-sus or z-sus boards. Do you or anyone here have experience with troubleshooting them? If there is a parts kit or something I would be comfortable replacing the components, if not the entire boards are available on ebay.

      Comment

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