Help with Vizio P702ui-P3 Black Screen

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  • Russ-DS
    Member
    • Dec 2019
    • 16
    • United States

    #21
    Re: Help with Vizio P702ui-P3 Black Screen

    I'll take another look at the cables, but didn't see any folds or pinches, etc. The picture on the right side during the <1 min before it shuts down (powers off TCON and backlight, the rest stays up) is actually like old school snow/static. I have not tried it with an actual source, and also do not use the speakers so have had them off. I can try that hopefully tonight.

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    • Russ-DS
      Member
      • Dec 2019
      • 16
      • United States

      #22
      Re: Help with Vizio P702ui-P3 Black Screen

      I can't seem to find any issues with the cabling. I've been able to confirm that the left half has a perfectly good picture and has sound with a good source for about 1 minute, at which point it seems to do a partial reboot (based on the SPDIF light), followed by no power to TCON and no backlight until power is removed for a long time. While the left half is working the right half is static.

      Comment

      • budwich
        Badcaps Legend
        • Jul 2015
        • 3097
        • Canada

        #23
        Re: Help with Vizio P702ui-P3 Black Screen

        hmmm... that would appear to indicate that "most" of the main board is working as sound and picture are there. Not how the "bits" move from the main to the tcon (ie. which cable on the lvds cables is which and indeed which portions / pins are used.

        did you try any heating to see if things change?

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        • Russ-DS
          Member
          • Dec 2019
          • 16
          • United States

          #24
          Re: Help with Vizio P702ui-P3 Black Screen

          No, I didn't try heating things up. The main board was getting plenty hot on its own while powered up.

          I just bit the bullet and ordered a new main board off ebay with a return policy, so we'll see what happens on the ~29th.

          Thanks again for all the help.

          Comment

          • Russ-DS
            Member
            • Dec 2019
            • 16
            • United States

            #25
            Re: Help with Vizio P702ui-P3 Black Screen

            The new main board arrived and has resolved the issue. All is working again. Wish I could have found the bad component, but suspecting it was one of the ICs and not something simple. Thanks again for all the help.

            Comment

            • budwich
              Badcaps Legend
              • Jul 2015
              • 3097
              • Canada

              #26
              Re: Help with Vizio P702ui-P3 Black Screen

              good work!

              Comment

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