Wondering which pat I should repair; TCON or Main Board

Hi Pat, I'd test F1 on the tcon board to see if it's blown, if it tests ok try a main board, only way to know for sure if the main is outputting video to the tcon would be with a scope

The series set you have has the power and main board as a combo and has had lots if failure issues so I'd try replacing this board, as long as your backlights stay on we can cross those off the list of possible issues

It could be a bad main, power or tcon board, you will need to do some voltage tests to see where the issue is at or just replace a board set if one is available. There is also a slim chance you have a bad panel

A lot of people miss understand how the backlight circuit in the power supply works, you will get voltage testing to ground as its the B- side that's switched, the chassis ground and backlight B- are not connected. If you tested each LED strip and they're all good there has to be something else going on other than the typical backlight issue we see on so many LED sets.. I'm not an authorized service center for this brand TV so I don't have a service manual, if this set has separate power board and main test the bl_on pin on the power supply, you should have around 3.5 volts there, that's what tells the back light section of the power supply to turn on.If you don't then it's a bad main board

Defective power supply

Maegan,
You have already changed power supply/led board and main board. What is left now is the tcon and scaler board. Please try tcon.This may solve your problem. By the way, there is a systematic way of singling out the faulty board. A little research on this will save you save you time and money. Good luck.

Have you checked your power supply voltages?...if so what are they?

Sounds like T'Con board fault. Check and replace it. If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/

Hi, I just read what you have posted on my LCD TV troubleshooting guide, it does not sound like bad T-CON board because you do not get the sound, you disconnected the main T-CON connector from the main board and get the glowing screen but you still do not hae sound.
In the LCD TV, you can discoonect the backlights inverter board power cables (cables from power supply to the backlights inverter board), and the T-CON board cables from the the main board to the T-CON, you should still get the sound since there are no feedback singals from the T-CON or from the backlights inverter boards to tell the main board that they are bad or not.
If you are 100% sure that you do not have sound on all the input modes then I would suspect the main board problem.
At least the backlights ineverter is good.
Do you get the 12v at the T-CON board surface mounted fuse?