42pc3dv Zsus Question

[ad1982]

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!

[ad1982]

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.

[tom66]

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.)

[ad1982]

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!

[tom66]

Re: 42pc3dv Zsus Question

Can you see a place to check Vzbias (or Vzb) voltage? What do you read?