Try doing a system reset in your TV, according to the owners manual you have to:
If the TV does not respond to the remote control, front panel controls, or will not power on/off, press the SYSTEM RESET button on the front panel with a pointed object, such as the point of a pencil or end tip of a paperclip. The green LED will flash quickly for about one minute. When the green LED stops flashing, you may turn on the TV. The changes you made most recently, before using SYSTEM RESET, may be lost.
The system reset will reset your lamp timer and it also troubleshoots the TV, this should help out.//Owners Manual
In this link you can download the service manual for your TV:http://www.fixyourdlp.com/blog/tag/proyection-tvs/Note:
The service manual also has a troubleshooting procedure, check the lamp indicator pages//Troubleshooting the lamp
If your TV still doesn't work correctly, then try this troubleshooting links:http://www.fixyourdlp.com/forum/viewtopic.php?f=9&t=403http://www.fixyourdlp.com/wizard/wizard.html//More about the lamp
To learn more about the lamp click:http://www.discount-merchant.com/how-dlp-works-like-magic-a/141.html
To Learn more on the DLP TV click:http://www.howstuffworks.com/dlp.htm