You will need to unplug your TV from the power outlet and any power source for about 1 minute,then plug it back in. Check to see if the HDMI cable is properly connected.Or change it to a different socket. Do a factory reset.
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Apr 13, 2023 - Troubleshooting. 1 Check whether the lines on the screen are moving or permanent. 2 If the lines sway, check the input source (HDMI 1, Video, ...
Have you tested the backlights by removing the connector going to the main from power board, this will tell if the hot side of the power board is working and you will get backlights if they work?
This sound like an issue with the x-main board, if you unhook the power cable going from the power supply to the y-main board and you get VA and VS voltages there is about a 95% chance of the power board working ok, both the x and y main boards in this model set gave issues, one problem is going to be finding a board at a decent price, you can troubleshoot the board yourself, it's generally the mos-fet's that short, the ones that are attached to the heat sink. If you find some bad, replacement parts can be obtained from Mouser for a few bucks, they're easy to change with a soldering iron and some solder wick or sucker
A power board will never cause a sound delay issue, if it's doing it on all channels its most likely an input issue, such as your cable box, fire stick ect
This set is what's called edge lit, it has 2 led strips on the bottom of the panel, then a defusing screen spreads the light, you have some shorted LED diodes making the darker spots, new lamps should fix the TV as long as the diffuser screen is ok.
When you say getting 51 volts to power fuse, I assume you're using the red lead from the multi meter at the fuse next to the power plug, but where are you putting the negative lead from the multimeter? If you're using frame ground this won't give a correct reading, in fact you will get around 50 VAC, you need to use the anode side of the bridge rectifier to get a reading or the neutral side of the power line. Does the fuse test good? if it's good measure across the B+ capacitors but be VERY careful getting that measurement as it will be close to 400 VDC if PMW is active, voltages like that can be dangerous. If you had a power surge there is a good chance the hot side of the power board was hurt, easy fix may be replacing the board, another issue this model set has is corrupt data in the EEPROM located on the main board, this can make the set appear totally dead
