Lcd tv l22d400 can't start screen but audio ok

A lot of flat panel tv's have crapo capacitors from China, and they interfere with 'ready' circuits. Replace main capacitors on ps area, TV should come on.

That looks like a problem with the LCD ribbon cable, or the connector to LCD display.

11 inch world tec lcd no power adaptor is ok

I would suspect overheating of an electric component in the power supply of the lamp (backlight) of your lcd tv. bring it in for repairs.

I had the same problem and fixed it with a new backlight inverter board. It was a pretty easy install. The part is available on eBay. http://cgi.ebay.com/New-Inverter-for-Dell-W1700-17-inch-LCD-TV_W0QQitemZ400017456720QQcmdZViewItemQQptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116

You can accomplish this by unpluggin the tv for 4 hours. When you power it back up the internal software will revert to the original factory defaults.

If you are using a set top box this might be caused by turnig the box on at the same tie as you turn the tv on or slightly after you turn the tv on.  If you are using compnent or HDMI inputs the set needs to see the signal as it is turned on to know what formt the signal is in. 

I’m happy to help further over the phone at https://www.6ya.com/expert/dewayne_4a10eab6caecdb92

the invertor board faulty
Martin

I have samsung 40" LCD tv and it's happening the same thing. I turned it on and it last for 5 minutes and the screen went back but the audio is fine. I turned off and turned it back on it worked fine but an hour later it happen again.

If the Tv turns on (power supply is ok), screen lights up (inverters are ok) but don't get a blue screen, menu options, source options, or audio, it's most likely the main board (aka Motherboard) is faulty. If a DVD player is hooked upto the TV, check whether you can get audio from that (change the source using remote), in such a case it could be a problem with LCD Interface board. My $3 is on faulty Main board.