20 Most Recent LG 42LB5600 42" LED TV 1920x1080, 60 Hz, HDTV Questions & Answers

If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience.
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Line faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent. Faults to all LCD screen are similar, irrespective of its brand and screen size.

The main power supply regulator section circuit fault. Either it will be a separate board, or the part of main board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Pull up older posts.
http://electro-medical.blogspot.com/
It will be best to replace the power supply regulator board as card basis rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size.

The TCON board Or the LCD panel is Faulty. Can confirm by replacing the TCON board.
If you wish to get some details; check the site linked here. Pull up older posts.
http://electro-medical.blogspot.com/

I would check the capacitors. It is usually the capacitors that gave out. You can tell the capacitors are bad when the top part of it is not flat and it's bulging.

Chances are you have lamps in the panel that are bad

check in set up see if on demo or home

POSSIBLY NO FUSE IN IT TV REPAIR SHOP TIME

The fluorescent tube backlights are cutting out. Probably aging and causing the invertor to cut-out. Try a new invertor PCB otherwise the tubes are faulty and you would need to replace the display

Almost all TV's can receive digital (over the air) signals as long as you have a powerful enough antenna. This is different than the digital signals from cable TV, which are processed through the cable box then input into your TV (best way is HDMI connection). Check your TV manual for how to set up over-the-air broadcast capabilities.

call the company or reset the cable box if you have one or make sure it is the right remote