Panasonic TFTV5025FL LED supply self destructs

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  • dkneyle
    Badcaps Veteran
    • Dec 2013
    • 441
    • Australia
    #1

    Panasonic TFTV5025FL LED supply self destructs

    (Yet another that I am trying to diagnose by remote control.)
    I sold the power supply on Flea-Bay after writing off my TV because of a failed LED in the backlight string. Buyer had a TV with sound (and I suspect flash light test would have confirmed working LCD panel) but no backlights. He took a punt and purchased the power supply board which has the LED string supply integrated with it. He reported that the replacement board worked for about 20 minutes before failing with the smell of cooked electronics. So I'm suspecting something is killing the LED driver output. Now it runs at about 120VDC and the backlight LEDS are all in series. Does anyone have suggestions of what, in a fairly simple circuit, could be killing the power supply?
    Tags: None
    • sordids999
      Badcaps Legend
      • May 2013
      • 2152
      • uk
      #2
      Re: Panasonic TFTV5025FL LED supply self destructs

      Posting pictures of the back of your tv showing the boards with clear pictures may help you more with fixing your problem

        Comment

        • dkneyle
          Badcaps Veteran
          • Dec 2013
          • 441
          • Australia
          #3
          Re: Panasonic TFTV5025FL LED supply self destructs

          Mmmm, by "remote control" I mean I am trying to diagnose the TV that is 500kms from me.

          Best I can offer is topside view from image I took for E-Bay listing.

          But I'm looking more for any suggestions of an explanation. Two power supply boards die from overloading. The back light is a single string of about 60 SMT LEDs. Running on 120VDC.

          It's got me buggered (to use the Aussie vernacular).
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