42pc3dv Zsus Question

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  • ad1982
    Member
    • Dec 2013
    • 21
    • USA
    #1

    42pc3dv Zsus Question

    Hi guys, have a 42pc3dv that I think I have a bad Zsus on. Sometimes I can get it to power on with Y and Z plugged in, but it's not powering on properly right now. Either way, I get the same result as when I unplug the Zsus board. I've attached a picture of what I'm getting on the screen when it's powered on. Obviously only half of the screen is showing, but the half that is working isn't complete, so I was wondering if that would be normal. If you look at the top-right corner, you'll see it's a little bit blacked out even on the good side. And the menus/channel listing isn't crisp. Just wanted to make sure this is normal and would point to the Zsus board being bad (it's heatsink is cool to the touch, whereas the Ysus heatsink is warm). Also, when it was powering on with both boards plugged in, the screen split wasn't directly down the middle like in the picture, it was not a straight line.

    Thanks for the help!
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    • ad1982
      Member
      • Dec 2013
      • 21
      • USA
      #2
      Re: 42pc3dv Zsus Question

      Does the picture I attached look like what the symptoms might be with only the Ysus board attached? There's definitely something wrong with the Zsus, just wanted to make sure that with Ysus only attached it would still be grainy in the menus and a little black in the corner on the good side.

        Comment

        • tom66
          EVs Rule
          • Apr 2011
          • 32560
          • UK
          #3
          Re: 42pc3dv Zsus Question

          That looks like Z-sustain Vs and Va fuse blown. Z-sustain provides left hand side Va (for image) and common electrode supply (for good picture across whole panel.)
          Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
          For service manual, schematic, boardview (board view), datasheet, cad - use our search.

            Comment

            • ad1982
              Member
              • Dec 2013
              • 21
              • USA
              #4
              Re: 42pc3dv Zsus Question

              I did check the 2 fuses on the Zsus board and they're good, so I'm guessing the whole Zsus board needs to be replaced (or the hybrid chip under it). Does that sound about right to you? I do see some bulging caps on the power supply board that I'll replace for sure, but from what I understand the fact that it turns on when that board is unplugged and it also has a cold heatsink it is probably the board itself, you think? Thanks for the help tom66!

                Comment

                • tom66
                  EVs Rule
                  • Apr 2011
                  • 32560
                  • UK
                  #5
                  Re: 42pc3dv Zsus Question

                  Can you see a place to check Vzbias (or Vzb) voltage? What do you read?
                  Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                  For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                    Comment

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