Why does my Mitsubishi hc5500 projector only display a blue screen but still play sound?

Blue is probably the default "no signal" screen. It means that the projector is getting no signal.

Blue is probably the default "no signal" screen. It means that the projector is getting no signal..

One of the internal light filter (polarizer) has burned a hole in it. HEre is a video that show replacement in a similar machine. PArts were obtained for 150 from Mitsubishi. http://www.youtube.com/watch?v=A_wgbnArcu8&feature=share

Still a bad lamp

The problem is most likely a warped plastic housing around the color wheel. When the wheel is forced to stop, the projector will go to standby and the lights indicate a problem.

If it happens on other surfaces then it looks like your LCD module is damaged. It will have to be replaced.

Red and Green bliking with no picture means a service problem. But you might try cleaning the filters first and being sure that nothing is blocking air flow through the projector. Red status solid means replace the lamp, but that doesn't seem to be the indication.

have the store fix it you need a tech that has the right equipment to fix that. Since you say you replaced the lamp I assume you mean a LCD micro projector not an LCD Flat panel. There is a piece of equipment that a tech should have that can be plugged into the TVs circuit board and it can fix the spots with an electric pulse. I have seen in done on micro projectors in the store that i work by our techs. So my advise is have the store fix it before your warranty runs out.

the problem is in the light path starting with the blue input polarizer then the blue lcd hopefully its just the input polarizer. worst case you will have to replace the LCD block witch is expensive to do. the polarizer ia a speacialy tinted glass designed to help with the LCD's temp.