Tv blanks out then comes back on after the tv is on for awhile its the on and off button when you cut it back on itit shuts off

just make sure that your BACKLIGHTE is not adjusted to 100%. I found that in some sets with bad screen when the above is up to the above value it cut off and you have to wait until it cools down.

Try keeping the room at a cooler temperature to prevent overheating. also try to ensure there is nothing blocking the vents.

Is it overheating?

I have the same problem with mine. I can recreate the problem by stopping the small fan on the right side by the inputs. I'm not sure if its a heat problem or not. I already bought a new Sony Bravia but will continue to tinker with this for awhile.

Ur main video board backlight,is dying must be replace to solved this prob.

try using a master reset to fix this.
Sometimes after being used for awhile electronics tend to malfunction.
press and hold these buttons in this order....
power / volume up / channel down.
The tv should shut off after doing this.
Turn it back on manually.
This will reset the TVs internal memory chip.
I dont guarentee this as a permanent fix....but it worked for me.Good luck

even though lamp came back on and worked for awhile, it was a bad lamp. replaced lamp and set works

check the power supply sounds like its going out

Hiya this is how i got mine to work.Manually turn on the tv.
Press and hold setup on your remote till the light comes on and stays on.
Then press the tv button then release. The light will flash then continue to stay on. 
Now press and release the power button waiting 2 seconds before you press it again until your tv switches off.. you may have to press it for awhile.
Once your tv cuts off press the mute button and now your remote is set for your tv. 

found cold connection on board at tuner