Akai 42" PDP4294 plasma

The Akai is Samsung brand--have you when using that input that does not work gone into the menu and "selected" it and or highlighted it?

On what board and what transformer? Power, standby, Driver????

Do you keep it on all of the time.

here's a possible fix, but at your own peril.

http://www.wikihow.com/Fix-a-Stuck-Pixel-on-an-LCD-Monitor

Try unplugging it for an hour or so or try change sources , if the computer ever fell asleep while it was plugged in it is possible it triggered a sleep mode in the tv. Most will do such a thing. It is doubtful that the computer caused any damage to it but i would advise against using a plasma tv as a computer monitor because burn in WILL eventually occur with a static image left on the screen constantly.

Here's the cheapest place I can find. $54.95
Here's the link:
AKAI PDP-4294 PLASMA TV REMOTE CONTROL

change the color wheel.

if the pic is there when a flashlight is held to the screen the backlight/inverter has failed.

I repaired mine. It had the same problem. Could be power supply. If you open it then maybe I can help.

I have an Akai PDP4273M that developed the same problem. Checking around some of the av forums, I found a couple of threads that indicated it could be dust or bad contact around the ribbon cable connections on the video control board. I removed the back, loosened the ribbon cables on the board and used my small compressor with an air gun to blow out the dust all around the board and the ribbon connectors. Reconnected everything, turned on tv and stripe did not come back. Problem fixed! Nice and cheap solution.