Facing TV Problems? Ask a TV Technician.
Hello, How long have you owned the set for and when did the problem occur?
Also, what sources are connected to the set (DVD player, cable box, etc.), and is the white line there regardless of source you select?
How thick is the line on the screen as well please?
Hi Tim- thanks for the question. Can you reply back to the info request above please?
Okay thank you. Please unplug the TV from power, and also remove the HDMI cables from the back. Wait 10 seconds and plug them back in and plug the TV back in. Check both the Roku source, and also the Cable source, and let me know if BOTH exhibit the line please.
Is the line still there on both sources please?
This means the line is generated within the TV. There's no adjustments to remove the line. It's either caused by the T-Con (LCD controller) or the LCD panel itself (which is not repairable). Given it's a 1/2" thick- there's a good chance it's only the T-Con that needs to be replaced. Does the line move or flicker at all- or is it completely stationary?
Okay, the only attempt at a fix is to replace the LCD controller board (T-Con) in the set- as there's no way to determine if the -Con or LCD panel itself have failed. The Mainboard is not anything I've ever seen cause this line. Vertical lines are generated by the T-Con or the panel itself. You can try to touch up the solder joints on the mainboard, but I honestly would not pursue that route myself.
I am unable to find any parts at all available for that model number. Are you in the U.S. like the site shows? Or is there another model number off the back of the TV?
TWFM-BOO3Dn is a Wi Fi chip, and I can find a manual for a 42LT770H- but not a single part for this model.
The only thing you can try is remove the back of the TV and take a picture of the back. See if there's a metal shield in the upper middle of the screen. If so, the T-Con is underneath that shield, and there will be a part number on it.
I'm signing off for the night- as it's late here, but you can postback at any time, and I will continue tomorrow morning.
Did you ever end up getting the back of the TV off?