My westinghouse flat screen tv - i turn power on picture comes on for a few seconds and goes black - sound still works - any suggestions?

http://www.fixya.com/support/t10640288-westinghouse_ld_3235_picture_goes_in_out
did you tried that?

HI:
Seems have no Y-Drive, Check and or replace the Main Y-sustain board.

Reset the tv and the cable or satalite boxes,replug it back an hour later let the tv reset it self back to factory setting and the boxes upgrade it software.The tv should work now.Not,than yes.It the Tuner main board.

it has problem in picture tube

Hello, it sounds like you need to replace the inverter board on this unit. I would recommend opening the unit from the back cover, get the part # for the inverter board (long green board normally running accross the edge of the TV) and go to www.shopjimmy.com, they should have it in stock and if not you can try www.invertercentral.com, they should also have it.

Look for Bad capacitors on power supply board they will be vented or swollen on top 220uf 10v 330uf 1000uf 16v

Mainboard damaged.

Some solutions to this same problem were posted here, hope this helps.

westinghouse_w32701_27_in_hdtv_lcd
power on no picture good sound and channel page up and down works
on background u can see dark picture

I had the same exact problem.
I removed the bulb and cleaned it. There is a small screen at the top of the bulb and it was covered with dust. Once it was cleaned I replaced the bulb and it solved the problem.
Thanks to those who posted the solutions