Have a 42LB5600-uz with lines in it vertical. Changed the T-CONN Board. What to do next.

There could be a bad connection or a processing problem. Unplug the video cables and another devices and things that are attached to your TV for about a few minutes and see if the lines are not there any more and if the lines still show up on your TV's screen then you need new cables. Or there could be a problem with the TV's screen or the T conn board then.

Possibly loose wiring going to tcon board

Watch video

https://youtu.be/prz9sNuxgWE

Or power switch is actin up

The tv that I have is an LG 42LB5600-UZ, but that wasn't one of the choices. The problem is that the television turns on... has a picture and sound, and then in about 30 seconds, the screen goes black but the sound continues. It is the same on every channel. It worked fine last night, but not today.

Only way to find out is to take the panel apart and test the LED strips with a DC power supply

The main board tube is gone, you need to replace the same from a service station

In most of the case, the problem is defective back lights LED strips inside of the panel.

If you hold a flashlight up to the screen do you see any image or video

most of the stuff from jimmy's its second hand ( not good working or working maybe) first and the last i suppose you got a problem with the power supply on the T con on the second i suppose you have a problem with the big chip in the middle the scalier :D

Hi,
Vertical colored lines usually means a bad panel. At the least it might be the t-conn pcb (a board connected to the panel). You might get lucky and just unplugging and replugging the LVDS cable (its a thin computer cable with lots of wires that goes from the main board (it has the audio and video plugs on it) to the t-conn board. You usually push in the clips on each side of the connector to release it. good luck! Panels cost more than the TV did.