I get a blue screen on my misubishi sl1 projector lamp and no signal appears on the screen

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

The unit may need cleaning. The lamp will shut off if the air flow is blocked by dust.

If you are talking about the actual image that is coming from a laptop being yellow instead of white, then this is caused usually by a bad signal cable running between the computer and the projector.
To be more specific: All colours in a projector get made up in some way between red, green and blue. White is all of these colours at maximum, yellow is made by red and green at maximum but no blue. If your image is Yellow when it should be white, then the blue signal information is not reaching the projector. This can also happen within the projector or computer itself but is less likely. If your using a VGA cable (15 pin cable) then blue is run through pins 3 & 7 (positive and negative respectively), see if your cable is either missing these pins on either end or if they are bent, although it's more than likely within the cable itself. You can test this theory easily by trying to put something blue on screen, if the blue signal isn't getting through then it'll appear black.
If changing the cable doesn't solve the problem try testing the computer by trying to use a different one, and test the projector by plugging in a monitor or another projector.

If you are getting a yellow screen without sending signal and just trying to get the "no signal" or "no input" screen white, then this won't be the case.

give more details , when you get blue picture ?
blue screen is indication that no signal is coming to projector so check your cable and try different connection, there is svhs and dvi input, try both.

here are some probable causes..
This appears to be an older model (over 5 years old) and LCD projectors turn yellow with age. It's just what they do
However, if you are projecting a computer signal or a component signal, a short in the blue signal of the cable can cast yellow hues over your image. The hue will cover the entire image as if you are viewing the image "through rose (or in this case, lemon) colored glasses" so to speak. That's an easy fix.

Harder fixes: the blue LCD panel is weaking and/or gone bad.

If you have a round yellowish spot in the middle of your screen, the diffuser has been overheated and is "burnt".

If you are connecting to a laptop then you may need to hold the function button down and press F1, F2, F3 etc. there should be a sign with the latop on there and a sign with an external device (monitor,PROJECOR)
hope this information was useful to you.

your display settings may be off, so change settings to factory reset and you may have to drop the resolution on your computer. you may also have a bad cable, so try a different cable.

Give input signal to the projector and see that if the menu appears or not on the screen.
if menu comes on the screen then put the backgroung color to blue, instaed of black.

if nothing comes on the screen, then the LCD panels are faulty.

Viren
RAVE SERVICES

Can you connect a computer (vga) signal to this projector? I'd like to know what your "white" computer screen does on the projector....example, Excel spreadsheet....

I am leaning towards these problems, a bad video card...or worse delamination of one of your LCD panels and possible polarizer burn in the optical engine.

Best Regards,
Steve

Hi there

Press the source button on your Projector until it reads RGB.

If this doesn't work , right click on your desktop and go to properties - check that your seconadry screen is attached in your advanced settings.