Insignia LCD TV NS-39L240A13 backlight comes on then off

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  • shelby5041
    Badcaps Legend
    • Feb 2009
    • 1504
    • united states of america usa

    #1

    Insignia LCD TV NS-39L240A13 backlight comes on then off

    hi

    tv turns on and backlight comes on and shows please wait graphic then after 2 seconds backlight turns off and image and sound still ok

    this is a ccfl style bacjklight

    no sepearate inverter board....all part of ps..i replaced ps since they are cheap and same issue...any ideas? bad ccfl tubes?
  • shelby5041
    Badcaps Legend
    • Feb 2009
    • 1504
    • united states of america usa

    #2
    Re: Insignia LCD TV NS-39L240A13 backlight comes on then off

    from l;ooking at a similar model 50 inch on here it seems the inverter board could be part of the ccfl assembly insdie the tv screen area ... not visable and maybe not repalceable...very odd tv...will have to take apar5t firther..its definitely not a ps issue

    Comment

    • Andrew F. Ali
      Badcaps Legend
      • Jan 2014
      • 2450
      • Trinidad & Tobago

      #3
      Re: Insignia LCD TV NS-39L240A13 backlight comes on then off

      Can you identify the P-DIM, BL-ON/OFF, 24V and GND wires on the PSU connector? If you can identify these wires, I could help you convert this to a LED Backlight TV.

      Comment

      • Unspun01
        Badcaps Veteran
        • Jun 2011
        • 333
        • Canada

        #4
        Re: Insignia LCD TV NS-39L240A13 backlight comes on then off

        I've seen this similar design on a 50" Sanyo TV with inverter board located inside the panel.

        The thin narrow board and all transformers on the board were ok, and it was in fact a failed ccfl lamp in my TV.

        You may have luck replacing the ccfl from another TV with same diameter of bulb and end-to-end length of ccfl electrical contact pins.

        Be careful removing the ccfl lamp from the delicate plastic retainer clips because they are easy to snap. In my case, I withdrew the ccfl lamp by pulling it to the left or to the right from each support and feeding the new lamp back in the same way (instead of springing the clips apart)
        Last edited by Unspun01; 04-29-2019, 10:14 AM.

        Comment

        • shelby5041
          Badcaps Legend
          • Feb 2009
          • 1504
          • united states of america usa

          #5
          Re: Insignia LCD TV NS-39L240A13 backlight comes on then off

          good news very very bad news...it was 2 bad ccfl tubes so i just used a wire to jumper it out and then backlights worked..but i broke lcd panel when i reassembled....initially i reassembled and was ok but i could see the lcd panel was not aligned properly so i reluctantly decided to take apart again to realign and yes i cracked the screen when i tiightened the screws and something wasnt lined up properly and screen cracked....i hate dealing with lcd panels..i have done this about 4 times..fixing tv then breaking lcd panel whne putting back together

          i threw tv in trash....i was very upset i spent about 3 hrs messing with this tv modifying it and being successful only to fail at the end during reassembly of tv.....not happy at all
          Attached Files

          Comment

          • shelby5041
            Badcaps Legend
            • Feb 2009
            • 1504
            • united states of america usa

            #6
            Re: Insignia LCD TV NS-39L240A13 backlight comes on then off

            man i am so upset right now

            Comment

            • shelby5041
              Badcaps Legend
              • Feb 2009
              • 1504
              • united states of america usa

              #7
              Re: Insignia LCD TV NS-39L240A13 backlight comes on then off

              so if anyone has same issue i had with insignia ccfl tv please check the ccfl tubes as it seems its a common issue on this brand or model tv.. and dont screw up like i did when handling the lcd panel

              Comment

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