No picture just comes sound

Try connecting a different device to the TV and check. You may also try changing the cable to connect the device to the TV and check. If the issue persists, try resetting the TV to the factory settings, then try power reset. To power reset the TV, please disconnect the power cord for a short period of time (approximately 1 minute). Then, reconnect the power cord and power on the TV. If the issue still persists, then service may be required.

also check the power cord wire coming from the back of the tv is loose from the tv side or perfect.

Your power jack is bad. The cable and DC jack are a one piece cable that can be unplugged from the motherboard and replaced. They are available on EBay for around 30 bucks or less and takes approx. 30 minutes to change out.

sounds like a bad color wheel

Bad caps in the power supply must be replaced .

Just try to reset so picture will come again, some LCD TVs have a reset button. If available and accessible, try using the reset buttons before using the steps below. Using the reset buttons can save time.
1. Unplug the LCD TV power cord from the power outlet.
2. Unplug any connected devices (DVD, Set-top boxes, etc...)
3. Press and hold the LCD TV power button for five seconds.
4. Plug the LCD TV power cord back into the power outlet and turn on the TV.
5. Open the on-screen menu to confirm that the LCD TV is responding again.
6. Turn off the LCD TV and reconnect the devices.
7. Turn on the LCD TV.

Hope it may help you;

Regards;
VOTIT

Hello there. I'm sorry to say that it sounds as if the element that actually energizes your screen is bad. It is most likely overheating. or quite poosible the power converter lost a resistor or 2.

I need to know how long do you have the tv?In the other word,approx. how many hours you have put into it?
Secondly,did you wall mounted the tv or setting it close the the area which there is not much room for the back of your tv to breath?
solutiondoct

The sound is coming from a failed flyback auto transformer. You will need to replace that.

I had the same thing - one long red flash followed by four short red flashes. Plugging and unplugging the power cord had no affect until I also unplugged all the cabled connections to the VCR and DVD player as well. Also, per the manufacturer's instructions, I unplugged the power cord from the surge protector and plugged it into the main wall outlet (which I tried first, but did not finally have success until I cycled the power cord unplugging process with all the cabled connections to the auxilliary devices unplugged as well).