Samsung plasma tv PS43D450A2 pixel issues

[Phlox321]

Hi guys. I have a Samsung plasma Tv with a wierd prpblem.its a samsung plasma PS43D450A2. A little history : I got the tv free from someone as the thought the power supply was bad and was about to throw it away. I check it and found shorted x main board. I found the diodes and igbts were shorted. After a long search for components i aquired them and replaced them. The tv then worked fine for a few months and about 2 weeks ago it started showing random yellow and purple pixels only on about the right of the tv. Its clearly cisible on a white screen but not as noticeable when watching a movie. And ideas what it could be? Ive read on this forum to up the Vs voltage abit since there are some purple patches on the display as well. I havent tried it yet. Any ideas where to start looking?

[dick_barton]

Re: Samsung plasma tv PS43D450A2 pixel issues

It would be worth checking all the solder joints on the Xsus board and ensure they all are good.
Search the threads for posts relating to adjusting some of the voltages. I can't remember off the top of my head which ones and by how much but it will be on the site here somewhere.
Finally I think that there may be an issue of panel aging if none of the above work out for you.

[ngth82]

Re: Samsung plasma tv PS43D450A2 pixel issues

Base questions first:

• What's the part number of your X-main board?
• Which parts (picture and circle them) did you replace a few months back?
• What were the PNs of the parts that you replaced?
• Were your replacements exact MPNs?
• Did you update the firmware of the TV after replacing the parts?
• Did you check your Vs and Va voltage values? Report back in this forum (don't modify them yet)

Some vendors (like LG) have a target waveform for the the panel charging and adjusting the voltages, and ramp rates may fix it. This could be a timing issue or the waveform isn't correct.

Here's the service manual for your TV, but i didn't see that information on the first pass: [LINK]