I called Mitsubishi (800 332-2119).
They will send the replacement chip (free) to an authorized service rep who then charges $200 to install. Awesome.
The repair guy installed the chip but then the TV won't power up. The error code says short circuit. He says the the mother board or the lamp engine is bad. What?! The TV was working before he touched it. Is it a screw up and/or BS?
It is my opinion the mother boards and light engines don't just mysteriously "go out". That there is a single component not working, which he should be able to diagnose (don't you agree?). I feel that he; (a) missed a step, (b) blew some component/screwed up or (c) deliberately caused the error code. He indicated that situation might cost more money. I stated my opinions to Mitsubishi. They are telling him to check again.
I had the same problem with my 65 inch Mitsubishi DLP TV. The white dots problem. I called Mitsubishi and they are replacing the DLP chip at no charge. They wanted me to pay $200 for the repair but I told them that if they wanted my continued business, they need to take care of it all. They agreed and now it is being done at no charge to me at all.