Samsung PN58C550 Blank Screen with sound

[tom66]

Re: Samsung PN58C550 Blank Screen with sound

OK, I figured out where the Vf (floating GND) and Vscan (Vad) are on the buffer chip. Test across indicated points. Try both ways, reverse probes. I expect the chip is short.

[bucash]

Re: Samsung PN58C550 Blank Screen with sound

Tom,
Sorry I guess I am unclear where to test from that picture. Am I testing two points or four points?

[bucash]

Re: Samsung PN58C550 Blank Screen with sound

Am I measuring this hole to the cap?

[bucash]

Re: Samsung PN58C550 Blank Screen with sound

Ok so I purchased the upper and lower Y board from a repair shop that was about an hour from me. I installed the new upper Y board and voilà Back to life! My question is should I replace both upper and lower boards at the same time? I still have an issue that was present before the TV broke down completely. It was a wide pinkish line that goes across the screen only when White is the dominant color. Anyone know what failure this is? Did this contribute to my blown board? Also should I check any other points before I put everything back together?

Thank you all for the help! I am grateful for any help on the questions above.

[bucash]

Re: Samsung PN58C550 Blank Screen with sound

Here is an example attached

[tom66]

Re: Samsung PN58C550 Blank Screen with sound

I completely missed your posts. (Don't be afraid to bump them, they can sometimes go to the previous page on busy days and I'll miss them completely.) Sorry.

Your pinkish line is caused by a low Vs voltage. Increase Vs by up to 5V, monitoring the screen carefully while doing so. Very common problem with these sets.

If the panel is working, no need to replace the other buffer.

[bucash]

Re: Samsung PN58C550 Blank Screen with sound

Thanks Tom! I went from 210 vs to 215 and the pink snow disappeared!

[docloonie]

Re: Samsung PN58C550 Blank Screen with sound

Hi, I have read many of your posts and am impressed with your knowledge of Plasma tvs. I have a Samsung PN58C550GIF / PN58C550GIFXZA PURCHSAE IN Feb 2011. Set working well until I heard a pop and then no picture but sounf works as do all controls
I checked the power supply by jumping the PS_on onto ground and the VS_on to +5v and all voltages check out. I checkd as many of the Mosfets s possible and they seem to work. I changed the X-min, Y-main and both Y-buffer boards with no help. The LED on the control board gives an error message: on 5 secs and off 1 sec. I get a very brief flash of light pattern on the screen(off center) when first turned on then nothing. I do not notice a glow in a dark room. Finally I jumped the power supply on and left the boards hooked up and still no picture.
Any thoughts? Thanks very much in advance!!
Ed

[Limited02]

Re: Samsung PN58C550 Blank Screen with sound

Hi, I have read many of your posts and am impressed with your knowledge of Plasma tvs. I have a Samsung PN58C550GIF / PN58C550GIFXZA PURCHSAE IN Feb 2011. Set working well until I heard a pop and then no picture but sounf works as do all controls
I checked the power supply by jumping the PS_on onto ground and the VS_on to +5v and all voltages check out. I checkd as many of the Mosfets s possible and they seem to work. I changed the X-min, Y-main and both Y-buffer boards with no help. The LED on the control board gives an error message: on 5 secs and off 1 sec. I get a very brief flash of light pattern on the screen(off center) when first turned on then nothing. I do not notice a glow in a dark room. Finally I jumped the power supply on and left the boards hooked up and still no picture.
Any thoughts? Thanks very much in advance!!
Ed

I know this is an older thread, but I have the exact same TV and issue as you as far as the screen flashing black and white static for a second when first turned on. Did you end up getting it fixed? The TV was perfect until I decided to do the Vs voltage increase to stop the purple glare and accidentally touched the left y-buffer board when stepping around the TV. Caused a spark and now nothing. Replaced both the y-buffer boards and y-sustain board with no luck, but as mentioned now the TV flashes static for a brief second before going blank.

@Tom66 ^