Horizontal green lines appear now and then; not clear picture

The picture shouldbe free of vertical or horizontal lines.

1. If the lines are present on the TV screen, press the SMARTbutton. on the remote control and select Settings> SUPPORT > Picture Test.
2. This menu will appear on the test picture. Select whichoption best describes the result you have.

https://www.lg.com/us/support/help-library/horizontal-or-vertical-lines-tv-CT10000020-1387209695776
A single set of horizontal lines could indicate damage, a graphics system failure, or loose internal video cables. Broken signals from cables or graphics hardware creates impurities in reproducing an image on an LCD screen, conditions that often manifest in the form of vertical or horizontal lines of color. https://itstillworks.com/causes-horizontal-lines-lcd-panel-37988.html

These horizontal lines are vertical flyback lines and would indicate
one or more of the tubes cathode drive circuits are defective.
As the picture is predominantly yellow this would indicate excessive drive to red and green guns. Check the red and green video output stages especialy any clamping diodes.regards from Vintie

Somehow when switching between the tv and the dvd my wife encountered the pink and green, thin, parallel, vertical lines on the screen. The picture was visible with the lines. I turned the tv off and on but the problem persisted. Unplugged tv for about two minutes and after plugging it back in and turning it on the vertical lines very gone and the picture was back to normal.

Check the 1.8 ohm resistors,located in front of ICs. Try replacing all 3 of them.

my acer lcd 32" tv just recently went of the blink. It has vertical, horizontal lines and fluro green screen. please need some advice...

Due to vertical section failure horizontal line apprears. You did not mention about picture. Green horizontal line means with picture or without picture. With picture means there is some leakage. Without picture only singe horizontal line means vertical section totally not working. Particularly green horizontal line means maybe leads to jungle ic failure. Please mention your simptom clearly what you get and what you will not get both video and audio. It will be helpful to answer. Based on your question this is my small information.

intermintence in vertical IC deflection its a job for experienced tech need to look for that circuit and do fine job resolding that IC

Picture displaced vertically, picture too high or low
This problem was cured by entering the service mode (menu then 4,7,2,5), then pressing the green fastext button to access geometry settings, selecting VP1 (vertical position) and adjusting as necessary
Vertical line at the left of the picture
Replace L506 on A board, replacement part number 1-407-366-00

I have not fixed it yet. But I have identified the chip that is causing the problem. If you have a service manual scan it and post it please, so I can show you the chip.

this symptom, sometimes called the tube light effect, it is characterised by a bright thin horizontal line across the middle of the screen. this symptom is caused by a breakdown in the vertical deflection circuit. hence maybe the trouble maybe in the vertical oscillator, amplifier or output circuits. but if all i have said is not clear to you, better bring it to a qualified tv technician. good luck!