Why is my tv making a humming sound and showed no picture?

you need to explore menue for tv options and select the proper input as well as other options.

Well that humming sound is indeed the color wheel.

This DLP tv have a colors wheel.The tv colors wheel,it dead.Have loud humming sound,motor noises and pictures flashes black&white within a picture.The colors wheel is dead and is spinning off of it axis and hitting of it sides motor walls.Tv must require a replacement of a colors wheel.Hire a tv tech. to do the job.The tv colors wheel is hard to replace.The tv colors wheel sit behind many manchanical parts,must take out even before u even can replacement the colors wheel itself.

it might be over heating

Actually that humming sound was not the lamp, the humming sounds come from color wheels when they're going out, and since the color wheel is part of the light engine system and it's not working, that's why you don't have an image, you'll probably ask your self why, since it's not the lamp.. the thing is that the light engine system is componed by lamp, ballast, color wheel and dmd board, so when one of these doesn't work, there will be no image reflected, because they work together

That sounds most like the color wheel,
to change that you need to have some skill in electronics, I would recommend to take it to a shop

Your color wheel needs to be changed. Mine just did the same thing. I changed mine, and the buzzing sound went away, however now my picture washes out with light or yellow colors. The darks look green and purple also.

The TV usually hums when the backlight setting is too low. So turning it up should get rid of the problem. To do this please follow these instructions:

1. Turn the TV on.
2. Press the Menu button on the remote, located right below the channel changing button.
3. Press the down direction button, located at the middle of the remote. Press that button until the backlight is highlighted.
4. Press the right direction button until the backlight is at 100.
5. Press the OK button and then the Exit button until you get back to your picture.

The horizontal output transistor drives a transformer that gives you the high voltage to light up the picture tube,either the transistor or the transformer have gone bad,sometimes both have to be replaced and sometimes the transistor fails for no reason by itself.Be safe and call for help if you are not familiar with tv service.