Hi

THe most likely problem you are having is bad capacitors on the circuit boards in the light engine. There can be multiple of these capacitors failures on different boards in the light engine that causes communication problems between boards . Repair of this problem is difficult because it requires breakout cables to operate the light engine once it is removed. At one time Mitsubishi had a program where you could remove the light engine and send it to them to be rebuilt(capacitors changed). The biggest problem was the cost of the rebuild was $350 to $400 , plus shipping costs. In addition to this if you are not trained on this tv , you would have to pay a local technician the remove and re-install the light engine. You may want to contact Mitsubishi and see if their rebuild program is still available. Sorry for the not so good news.