WHY DOES THE LASER COME ON FOR ABOUT 5 SECONDS AND THEN GOES OUT.

does it have daytime running lights that sensor could be bad or signal light switch ...signal to the opposite side light goes out to see if comes on

Check your input voltage as close to the radio as possible. Sounds like a low voltage problem.

It sounds like a plugged or restricted exhaust vent or blower wheel might not b spinning, check blower and belt:)

Most likely you either have a defective backlight inverter, bad back lamp. Based off of your model #, I'm gonna lean towards a back lamp.

The deflection board needs replacement. You need the PSB260 deflection board available from www.tvrepairworld.com

Is it under warranty?
You may have either the power supply problem or backlight inverter board problem, please se my pictures and troubleshooting guide below:
http://s807.photobucket.com/home/budm/allalbums
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
Parts: try www.shopjimmy.com or Ebay

Make sure you have the correct drivers install for you video card. Also, check to make sure your resolution is not set to high for you video card. To get to resolution; right click on Desktop > click Properties > press Settings Tab, from there you can move the slider to change your screen resolution (try different resolutions until it doesn't shut off anymore).

Let me know.

Brand, Model, is it an LCD, Plasma, or Projection TV?

Pioneer Model SDV77 Turns Of immediately Indicates DVD 5.1 CH Error DVD 3.3 Error