Hi, my name is mark, I had the the same problem for weeks now on my bush TV. model No-Ws6680Sil/C7 ,
My tv has colour but bottom left a green patch and top right purple patch of colour. The simptoms where getting progressively worse. So today I thought search the net ,and I come across your comment chris(above). I found the thermistor on the board. A little sign of heat on the circiut board by the side of the it. thought I would resoldier the connections. Luckerly this did the job. THANKS TO YOU.
Repaired the tele 1 hour ago. its looking good.
Mark, February 2009