Samsung Plasma (PN58A550) Intermittent Picture Dim/Fuzzy

[Atlascopco]

I have a Samsung PN58A550 plasma TV that I use rarely.
Recently, the picture quality has become very dim and fuzzy.
Another thread for a LCD TV called the quality "solarized" and I agree that is also a good description of what it looks like.

The weird thing is the TV will, rarely, pop back into full brightness/colour/quality but only briefly.

The problem is not input specific and it affects the menus as well as the input content.

The picture quality is similar to this: https://www.badcaps.net/forum/attach...2&d=1402011190

But then can bounce back:
https://www.badcaps.net/forum/attach...4&d=1402013630

From what I've read, the ZSUS/X-Main is responsible for charging pixels and therefore could be the culprit - I just need some more direction. Am I right that this is the problem (Or is it the YSUS?) I've taken out the two boards but they appear (to the naked eye) to be fine. I have a volt meter but am not sure where to check.

I also discovered a thread where someone seemed to be having a similar problem with an LCD TV and the issue was Tcon - but again I'm not sure if that's related.

Just looking for assistance in narrowing down the problem.

[Atlascopco]

Re: Samsung Plasma (PN58A550) Intermittent Picture Dim/Fuzzy

Here are some photos capturing the difference in picture quality when the TV is intermittently working at full strength and then when it is running dimly.

[capkid]

Re: Samsung Plasma (PN58A550) Intermittent Picture Dim/Fuzzy

My guess would be the X-main. I'd start first with checking the output voltages from the PSU to the X-main. I'm unsure of your familiarity with checking voltages, so I'll assume you have very little experience. You can measure voltages at the power supply test points by placing the red probe (positive) on the test point and your black probe (negative) on a metal part of the TV chassis. Your meter should be in "DC" mode. The voltages I'd check first are VS and VA. Also, be careful about removing and re-installing boards, as the caps on the boards hold a charge.

Here's some service info: http://www.toms-service-manuals.com/...&Search=Submit

Edit: The VS and VA voltage specs should be listed on the panel sticker.

[Alastair E]

Re: Samsung Plasma (PN58A550) Intermittent Picture Dim/Fuzzy

Check for dry-joints on X-Main particularly ER coils....

[Atlascopco]

Re: Samsung Plasma (PN58A550) Intermittent Picture Dim/Fuzzy

Thanks for all your help. I checked the X-Main for bad joints but there's nothing I can see at eye level. Voltages appear to be within normal parameters. Given the cost was alright I bought an X-Main off of eBay. I'll swap it out when it arrives and see if the problem resolves.

Thanks again for the suggestions and help narrowing down the problem to a specific component.

Cheers!

[Atlascopco]

Re: Samsung Plasma (PN58A550) Intermittent Picture Dim/Fuzzy

Hi guys - so I ordered a new X-Main off eBay. Swapped out the one in my TV and the problem remains the same. Either this X-Main is also faulty in the exact same way (a possibility) or else the problem lies elsewhere. I noticed another thread on here where the problem was supposed to be the X-Main turned out to be the PSU.

Can anyone comment (based on the pictures and description above) whether they think the PSU could be the source of the problem? Any more help in diagnosing this malfunction? Your help is greatly appreciated - Thanks.