Hisense LCD42V68PAM weird picture no BL

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  • paulstef
    Badcaps Veteran
    • Dec 2013
    • 724
    • Canada
    #1

    Hisense LCD42V68PAM weird picture no BL

    Hi guys,

    Front LED turns from red to blue, then blinks 6x red then stays blue, mainboard doesn't turn on the backlight and TV becomes unresponsive after power on. When I force the backlight on I see only a few square inch large noisy picture without any content.

    All voltages on the board are present, 12V, 3V3, 5V, 2.6V, 1V. Crystal for uC oscillates at correct frequency 27MHz but forcing it to stop doesn't do anything. It looks like the uC FW doesn't run...

    schematic is attached

    Any ideas?
    Attached Files
    Tags: None
    • CapLeaker
      Leaking Member
      • Dec 2014
      • 8148
      • Canada
      #2
      Re: Hisense LCD42V68PAM weird picture no BL

      Probably the main IC, flash or the ram. did you check all the regulators and ldo's? Maybe try some heat or freezer spray (can of air upside down).

        Comment

        • paulstef
          Badcaps Veteran
          • Dec 2013
          • 724
          • Canada
          #3
          Re: Hisense LCD42V68PAM weird picture no BL

          Originally posted by CapLeaker
          Probably the main IC, flash or the ram. did you check all the regulators and ldo's? Maybe try some heat or freezer spray (can of air upside down).
          yes voltages are all there, heat has no effect, cooling spray is out.

          too bad...

            Comment

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