Samsung PS43D490 red pink snow

[homerclone]

My First Thread :-)
Hope this has not been asked before (I did a search but could not find anything)
I have a Samsung ps43d490 3d tv and it started to show a pink/red pixel snow all over the screen.(please see pictures)
I went to Samsung website and installed the latest firmware for tv by usb but this had no effect.
I removed the rear cover from tv and read the vs/vscan settings for tv
should be va-58 vsc-185 vs-207
now to get rid of the snow I had to alter these settings to-
va-58 vsc-206.4 vs-209 and im getting a good picture.
My questions are
1. will this cause damage to tv by raising the settings?
2. is it week capacitors that causing me to raise these settings?
3. should I just change the boards?
Thanks for your time guys and girls :-)

[tom66]

Re: Samsung PS43D490 red pink snow

I would avoid setting Vsc so high; can you check what Ve measures? It's on X-main board.

[homerclone]

Re: Samsung PS43D490 red pink snow

Hi tom
Thanks for your reply but I cant see a test point marked ve?
on label it says ve = 0 ?
I sent pic of board I think is x-main (im a computer tech not tv tech so I might be a bit slow on this)

[homerclone]

Re: Samsung PS43D490 red pink snow

sorry tome I see ve on pin no.4 of grey cables going out the board 106.6 v
Does this help

[tom66]

Re: Samsung PS43D490 red pink snow

Ve = 0 means it's a free voltage (unspecified) not 0V. Confusing!

I would try upping Vs to 211V and dropping -Vsc to the lowest point of misfire. It is a known issue with Samsung panels (red diffusion.) Increasing -Vsc may damage Y-buffer board.

[homerclone]

Re: Samsung PS43D490 red pink snow

Thanks tom
Ve is showing 106.6v on terminal
Do you think replacing X & Y board would fix the issue or maybe is should order them in just in case it blows a board ?
Thank for your time
Mark

[tom66]

Re: Samsung PS43D490 red pink snow

I would try upping Vs to 211V and dropping -Vsc to the lowest point of misfire. It is a known issue with Samsung panels (red diffusion.) Increasing -Vsc may damage Y-buffer board.

Ve is OK, that is within range (80~120V.)

[homerclone]

Re: Samsung PS43D490 red pink snow

Thanks very Much tom
I have raised vs to 211 but I cant drop vsc the pink snow gets worse on a green screen.
If I change the x & y board do you think this will cure it?
would I also need power board?

Thanks for you time you are most helpful

[tom66]

Re: Samsung PS43D490 red pink snow

I do not think changing the X/Y-main will help. I think you will just have to set -Vsc to as low as possible and hope it does not fail, really strange though. Did you apply the Samsung "Red Diffusion" update? What software version is the TV running? I can't help but think the problem will get worse over time and you will need to increase -Vsc more until the buffer board is possibly damaged.

[homerclone]

Re: Samsung PS43D490 red pink snow

firmware version
1029.0 Upgrade File(USB type) 11 Dec, 2013

cant see the Samsung "Red Diffusion" update?

Hope this helps

shame I really like the picture on this Samsung and don't want to change it

[tom66]

Re: Samsung PS43D490 red pink snow

Sorry, my error, red diffusion is for C450 series. Seems like you will have to leave it as it is.

[homerclone]

Re: Samsung PS43D490 red pink snow

Just a quick update. I ordered new x-main and y-main boards from PARTS4U both boards sent were faulty :-( .Cant get hold of them as they do not reply to my emails or phone messages. So I order some more boards from eBay seller sivill123 He was very helpful and sent boards to me the next day. I have fitted the boards and set the vscan and vs setting to the settings labelled on back of tv.
The tv is now working fine.
I am well happy :-)
Big shout out to and very big thumbs up to sivill123 and a very big thumbs down to PARTS4u.me

[jbfr_54]

Re: Samsung PS43D490 red pink snow

Hi all,
I have yellow (mostly) and red sparkles on screen specially on dark images, all dependant of image content. Brilliant clear images (like a partly cloudy sky) do not show the snow.
Nominal voltages of panel are
Vscan -185
Vs 207
Va 57,6
Ve unmentioned

When the defect is showing I have measured
Vscan -183,6
Vs 206,1
Va 57,6

To get rid of the defect, I had to adjust to
Vscan 187,3
Vs 207,9
Va 59,6

Some sparkles still show, this is the very limit.

A better combination is
Vscan -186,1
Vs 210,4
Va 60,3

My question is about the risk for the panel or the Y-main / X-main or even X-address electronics.
What is the most dangerous voltage to increase ?
Thanks for any advice.
Jean