Vertical lines on LG-DU-42PX12X

I know this post is old,
But I had the same problem.
I was able to fix it.
Heres a write up I did on the "How To".
I added pictures and diagrams too.http://jasonkoller.blogspot.com/2011/02/lg-du-42px12x-plasma-tv-fix.html

I have the same problem the pic went out but have sound. where do i go to get the Yboard? do i need a special number off of it or something? I took it to repair shop and he said it would be like 500 dollarss to repair. but i see all kind of yboards on ebay for like 150?? how do I know what one to buy?

Hello; I am John at J D Electronics in Poland, Maine. I have an LG TV that was donated to me. It is a plasma model DU-42PX12X. It had 1 inch wide red and green vertical bar on the right and a blue and yellow on the left. These bars appeared intermittently. pressing on the control board would make the bars go away. I have read many blogs on this problem and they all say to replace the control board located under that huge A / V input board ( held in by 4 screws on the large aluminum frame). The original part is # 6871QCH038A The replacement ends with a C instead of an A Aprox 90 to 135 dollars. This board is used on many different LG and Zenith models and is a HIGH failure rate part. I like to know WHY parts/boards fail and I found out why this board fails. There is a large square IC in middle of the board aprx 1 1/8 inch square. This type of IC is called BGA or Ball Grid Array. The solder connections cannot be seen , since they are under the IC . This IC was not properly soldered at the factory and that is why hundreds of these sets failed. I used my hot air soldering station on it's highest setting to heat up this IC . The IC must be directly heated from the top and some heat on the bottom of the PC Board. Liquid flux should applied to the 4 side edges of the IC prior to heating. The bars are now gone! To get to this board, remove all perimeter screws and all middle screws of the back cover. The A V board will hinge back to expose the control board if you unplug the cables to the side inputs and the one to the button board. The set will still run face down on a table with something to prop up the bottom screen so you can watch the bars. If the set was run for a long time with the bars, there will be some darkening where the bars have " burned" the screen. This is perminent, but usually acceptable.

FIrst of all this is a plasma set and thus does not have a "convergence" board. This could be as simple as a bad cable connection inside the set or a failed supply for one half of the plasma panel. If the unit is no longer under warranty. try removing the back and reseating all of the cables and connectors. Since the signal levels are extremely small inside, it doesn't take much to cause a problem.

Update this with your results and we'll continue as dictated by the results.

Dan

Another "same probelm"

My set has encountered this magical 50/50 split screen and it seems to be quite a problem since I am not the only one researching this issue. LG was of no use because of course it is just out of warranty. Any solutions on fixing this or am I out of money in buying a new plasma?

the actual problem are the solder balls under the chip it can be fixed easily by reworking it, we have done it in a few dozens tv so far with excellent results the usual problems are: red vertical lines , one half of the screen not working, color lines and it usually cost only the time to perform it.
azhdtv at 85040

Since I haven't heard back ,I am clearing this from my queue. Best of luck.

Check within you area for a reliable LG repair center. To fix the problem of the blue, red or green vertical line you just need to replace the control board PN 6871QCH038C. The part cost about $150.00 and a honest repair center should not beat you up to bad on the labor. Good luck and Good viewing.

I had the same problem on my DU-42px12xc. Red, green , and blue lines vertically on the right side of the screen. I found a loose solder connection under the inputs board on a resistor. After re-soldering, everything was crystal. I'm happy I grabbed this tv before my work threw it out. Be very careful when soldering SMT components. Use proper equipment. I had to troubleshoot while the tv was on, so I was extremely careful not to short anything out.

I pulled the inputs board out to gain access to the "Y-axis" pins.
resistor located under the inputs
I started pushing on the resistors 'till the color lines started working correctly, and re-soldered the four resistors.

I had the same problem and fixed it by replacing the control board. It's a little nerve wracking, but required only simple hand tools. If you'd like to see detailed pictures of the repair check out my blog.

http://greenrenovation.wordpress.com/du-42px12xc-repair/