Toshiba 37XV500A low backlight intensity

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

    Toshiba 37XV500A low backlight intensity

    Have set backlight intensity to 100%. Output intensity of backlight is about 30% would be my guess. Unsure of history of this set. What is likely to be the cause? Worn out CCFL tubes or an inverter not putting out the required voltage?
    I haven't yet opened her up. If CCFL tubes then I'll write it off and cannibalise.
    Tags: None
    • Kg74
      Senior Member
      • Feb 2013
      • 67
      • Usa
      #2
      Re: Toshiba 37XV500A low backlight intensity

      Hard to tell without seeing the board. Does the unit have 1, 2, 3, or 4 bulbs? Maybe one side is out - not sure if possible but maybe 3 out of 4 bulbs are out. Open it up and post some pics.

        Comment

        • dkneyle
          Badcaps Veteran
          • Dec 2013
          • 441
          • Australia
          #3
          Re: Toshiba 37XV500A low backlight intensity

          Haven't got the set with me at the moment, so I can't send pictures. I opened it up and was presented with one of the most complex LCDs I've ever seen. Many, many circuit boards.
          I can only see two high voltage leads going to the CCFL tubes in the panel. So I assume they are just wired in parallel. The low voltage supply to the inverter is solid at 24V.
          I'm assuming TV's had a very hard life and the tubes are simply worn out.

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