Dynex LCD TV, no backlight. Suspect transformer ohm readings

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  • DasBub
    Member
    • Nov 2013
    • 15
    • Canada

    #1

    Dynex LCD TV, no backlight. Suspect transformer ohm readings

    Hey guys. I have a cheap-as-chips Dynex 22" TV ( DX22LD150A11 ) that powers on, passes the flashlight test (image on dark screen), but with no backlighting.

    The power supply board is a DPS-65TP-2 A and - after looking through the forum - I suspect the culprit is a transformer on the secondary side, T302, part number TMS94481CT.

    This page lists the resistances as 0.2ohms primary and 960ohms secondary. The values I've measured are [S1-S2] 267Kohms and [S3-S4] 980ohms.

    I'm guessing this means that the transformer is toast but I just wanted to make sure I'm not insane.

    Thanks!
  • DasBub
    Member
    • Nov 2013
    • 15
    • Canada

    #2
    Re: Dynex LCD TV, no backlight. Suspect transformer ohm readings

    Derp. Should've included model number in thread title. Sorry about that.

    Comment

    • budm
      Badcaps Legend
      • Feb 2010
      • 40746
      • USA

      #3
      Re: Dynex LCD TV, no backlight. Suspect transformer ohm readings

      Yes, that is bad winding on the transformer.
      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

      • DasBub
        Member
        • Nov 2013
        • 15
        • Canada

        #4
        Re: Dynex LCD TV, no backlight. Suspect transformer ohm readings

        Thanks for the sanity check! I'll order a replacement and let you know how it goes. Cheers.

        Comment

        • RWolfe8970
          New Member
          • Oct 2014
          • 3
          • usa

          #5
          Re: Dynex LCD TV, no backlight. Suspect transformer ohm readings

          I have the same TV as you however mine is saying please wait, Im thinking backlight inverter after doing some research any thoughts

          Comment

          • Amraks
            Badcaps Veteran
            • Nov 2011
            • 725
            • Australia

            #6
            Re: Dynex LCD TV, no backlight. Suspect transformer ohm readings

            "please wait" sounds like its trying to load firmware.

            Comment

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