I have a tale to tell, but I'll make it brief.
My TH-50PX60U 50 inch Panasonic Plasma stopped working about 3 months out of warranty. The power light would flash 7 times. I called Panasonic, no luck there. I went to one of their recommended service providers, and they said multiple boards had tested bad. They quoted me a price to fix it ABOVE what I paid for it. I asked them for the esitmate in writting, and paid them for the info, but I did not want to pay that much.
I found a Panasonic technical training manual on-line (I haven't been able to find it since), pulled the back and replaced 5 boards ($600). Upon starting it up, I discovered lines across the top. Eratic and oddly spaced. I undid the ribbon connectors that went from the SC and SU boards to the plasma screen, and made sure they were seated properly. And, lo and behold, the TV was working almost completely. I say almost because it still has one tiny problem, and, I can't find a post that says anything like this.
A single black bar, one inch from left to right, and halfway down the screen, in the right hand upper corner. It's more of an annoyance than anything.
I redid the ribbon connectors on the left side (in the back), and I also redid the ribbon connectors on the right. No change.
I can't find a way to eliminate it. I checked many of the connections I touched, but no change. It does not change it's size, shape, or location when changing the Aspect ratio.
Can anyone tell me what this is?