p50hdtv10a flickering with sound with Y-sus ticking

[DLinkOZ]

I was poking around other threads about this TV flickering, but most had no sound. Then a comment was posted, asking if it had sound and a ticking of the Y-sus that coincides with the flickering. Mine does, so I kept reading hoping for some good input. The thread went sideways and that question was never addressed.

So I ask - being new to this TV, can someone point me to some troubleshooting steps for the following scenario:

1. TV has sound from input device (connected to my DVR)

2. Screen flickers, though it seems as though it tries to make a picture during those brief instances when you're on the light side of the flicker versus the dark

3. The Y-sus has a corresponding ticket

[Glitcher]

Re: p50hdtv10a flickering with sound with Y-sus ticking

Common problem with this panel flickering is a Bad Y-sus, usually one of the two IPMs have failed.

[zdsh07p9]

Re: p50hdtv10a flickering with sound with Y-sus ticking

I believe your problem is the Ysus,

have you read this thread? https://www.badcaps.net/forum/showthread.php?t=18495

Coppell TV repair has a few repair options as well. I have had good experiences with Mr. Kolev at Coppell

[zdsh07p9]

Re: p50hdtv10a flickering with sound with Y-sus ticking

Glitcher beat me to it

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

I did read that thread, but the OP stated no sound so I wasn't sure I was looking at the same thing. I'll Coppell up for a repair, they're a quick 15 minute drive from my house. Just wanted a little sanity check that I was looking in the right direction. Thanks!

[zdsh07p9]

Re: p50hdtv10a flickering with sound with Y-sus ticking

...its been a long day, how do I delete this post? You should be good with the YSUS repair, if not come back and post it up!

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

Also, I while it's flickering I see the large vertical white bar in the center. Am I correct in assuming that one of the buffers is also bad? Reading through Coppell's blog entry about testing them now.

[zdsh07p9]

Re: p50hdtv10a flickering with sound with Y-sus ticking

https://www.badcaps.net/forum/showthread.php?t=31794

This is where glitcher replied about the white bar I believe, which as your post states is related to the bad buffer board

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

Using Coppell TV's blog, I tested the buffer boards and it seems as though the lower one is faulty. So I'll get the y-sus repaired and some replacement FETs and hopefully call it done.

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

Time to dig up an old thread - new y-sus and buffer boards had this guy going really well, just light use in a spare room. Until now, it seems to have a power supply failure this time. When I power it on, it tries to cycle up and clicks a few times on and off, on and off, then finally gives up. Checking things out, it's blowing a fuse on the y-sus board. Further checking shows that some of the 5v (not 5vsb) is shorted to ground. I completely isolated the power supply, and the short is happening there.

So my question is - does this seem right? No other voltages exhibit this short, and not the 5vsb. I find it in two different places, see pics. One is labeled 5vsc and the other is 5vctrl. Could it be as simple as a power supply? Nothing obviously bad on the board, but if there's anything I can test on it then I'm game. And as always, I appreciate the assistance I always get here!

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

I should note that in the second picture, the 5vsc is actually on the connector you can barely see at the right. The connector completely in frame isn't actually used.

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

A quick update - all 5v, except for 5vsb, is shorted to ground. So is there any non-common point in the 5v rail that differentiates between standard 5v and the standby 5v?

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

Pictures of the power supply, in case it helps. Some overall, beginning at the upper left and going clockwise to the lower left.

[DLinkOZ]

Re: p50hdtv10a flickering with sound with Y-sus ticking

I started tracing back the 5v line from one of the connectors. It's short all the way back to the smaller of the large transformers, T401 (center of the board). All pins on that side of the transformer have continuity, however it could be bleeding back from some other short (failed, cap, etc). Are there any obvious things to check in this circuit? As stated earlier, 5vsb is fine, but all other 5v is shorted to ground.