Tv problem troubleshooting

See troubleshooting guide for help
LG 49UJ6300 Service Manual (Page 25 of 65) ' ManualsLib

If your LCD TV or monitor has stopped working, or is displaying one of the following symptoms, then it's a candidate for some new capacitors
- Flickering screen
- Screen image disappears after several seconds
- Dim screen
- Slow start
- Power LED on, but no picture
- Unusual colors and/or lines
The primary cause of LCD TV and monitor failure is caused by faulty capacitors. You can examine the capacitors in your LCD TV or monitor and actually see if they are bad.
If they appear bulged on top, then they need to be replaced.
New capacitors will solve a host of problems in LCD monitors and TV's and will extend the life of your monitor or TV by several years.
Take it to a repair shop.

The controller board for the screen is going bad. check shopjimmy.com for replacement parts. It's not a difficult job to do. Once the back of the TV is removed, you'll see it near the center of the screen.

change your device cables or try to put at a pc to check if isworking your pc

it is the problem of the screen itself, you need to change the screen

That is the sign of failed T-CON board or bad DC feeding it from the logic board.
More likely to need new LCD panel, I hope you can take it back.
See my pictures to see if that is what you are seeing on your screen:
http://s807.photobucket.com/albums/yy352/budm/LCD%20panel/

Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors pictures: http://s807.photobucket.com/albums/yy352/budm/

Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague

Capacitors kit: http://lcdalternatives.auctivacommerce.com/ he can make you a set of caps for you.
Or www.digikey.com just make sure to use caps with low ESR, 105c, high ripple current, long life rating such as PANASONIC FM or FC series.

That sounds like either bad T-CON board or main board, need real in-depth troubleshooting.
You can the parts here:
http://www.shopjimmy.com/catalogsearch/result/index/?q=Proscan+42LED55SA+&stock=all

I hope it is still under warranty.

http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors: http://s807.photobucket.com/albums/yy352/budm/
Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague

Set the screen format using your TV's menu. Do not set the format of the screen using your provider's receiver. I had this prob with a few channels with a dish provider when I set the format with the remote from the dish provider. I picked up the TV's remote, went into the menu, set the format, problem fixed.

I went to the Sony support page for your model.(link below)http://esupport.sony.com/US/perl/model-home.pl?mdl=KP61V85&LOC=3
They are undergoing maintenance right now, so I couldn't find any answers for you. I would check back with the website to see if they can help you. If the Standby timer light flashes, you may need to have the TV repaired. There is a "Hot Topics" section for "How to troubleshoot television picture issues" that will probably be very helpful to you.

Unit is defective. If under 1 year, it's under warrantee. Send it back.