:geek: Hi,
Usually when this happens is related to a bad DLP chip, which is part of the DMD Board (Digital Micromirror Device) and light engine.
Watch this video that will explain you how your TV works:
http://www.youtube.com/watch?v=eD_xZcYQE50After watching the video you will comprehend that half of the DLP Chip is failing, you have a image since probably 1 column of mirrors is working and 1 isn't, 1 working, 1 not, 1 working, 1 not. And it creates the effect of dark image.
:arrow: Our sponsor's have the light engine:
http://www.discount-merchant.com/TOSHIB ... 180248.htmThe DMD board is the one on the bottom inside the metallic enclosure, the dlp is under the big heat sink.
There is people selling bare DLP chip's, but it will be hard to find one for a Toshiba TV.