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Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

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    Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

    OK so I've got a TV handed to me by a customer that I figured would be a cinch to fix based on previous experience with the symptoms. Turning into a real conundrum now tho.

    Anyhoo here's the skinny:

    Symptoms:
    Screen powers on, momentarily shows the Sceptre logo, then fades out to black in about 500ms. Audio continues to function normally, and the TV is detected properly on a Windows laptop via HDMI.

    Troubleshooting:
    My initial thought was that the t-conn board must be losing voltage and crapping out, but testing with a multimeter I'm getting a rock solid 5vdc on all the pins I should be. Thinking it still might be the T-Conn board I ordered a replacement from ShopJimmy and got that installed today, but still no video. Just for giggles I decided to test out all the voltages across all of the connectors that were labelled, and they all come out just fine. Lastly I figured the video processing cpu must have an issue (i'd seen similar things come up with the Samsung 305T) so I gave that and the ram chip next to it a reflow. Still no dice. I found a few posts on here about a Sony Bravia TV using the same panel that had an issue with the ribbon tabs coming loose, so I dismantled the LCD panel and tried putting some pressure on the tabs while I was feeding it video from a PS3. Still no dice.

    I'm all out of ideas. anyone got anything more I could try?
    Last edited by pyr0ball; 09-18-2013, 08:25 PM.

    #2
    Re: Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

    So the backlights are on but no pictures?
    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


      #3
      Re: Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

      Correct, backlights on, audio still working, but black screen

      Comment


        #4
        Re: Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

        I just started poking the voltage regulators after reading one of those posts in your sig. I think I found a bad regulator! theres two of the same model next to eachother, and a third on a different part of the board, and one has some different values. The last character on the second line looks like a backwards "L" which is strange.

        1117 B
        AD 221 |
        0.56
        1.80
        3.23

        ~and the other two~

        1117 B
        AD 221 |
        0.0
        1.23
        3.23

        I cant seem to find any fixed LDO's with voltage at 1.23, so I'm guessing this is an adjustable? I've got a local shop that sells SMD components so I'm going to go check if they have one tomorrow and try replacing it
        Last edited by pyr0ball; 09-18-2013, 11:26 PM.

        Comment


          #5
          Re: Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

          1117 B
          AD 221 |
          0.56
          1.80
          3.23
          This is correct, 1.25Vref + 0.56V (Adj pin) = 1.81V output pin (middle pin), within 2%.

          1117 B
          AD 221 |
          0.0
          1.23
          3.23

          OK @1.23V within 2%
          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


            #6
            Re: Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

            OK gotcha, I wasnt sure about that.

            Any thoughts as to what else I can poke at? Or is it just a bad panel?

            Comment


              #7
              Re: Sceptre X322BV-HD8AB02 / LTA320AB02 - No Video, Has Audio

              Just poking this thread again, I'm all out of ideas

              Comment

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