Chosen Solution
I was given this tv for free, in non working order. I got it running and powering on by replacing all the capacitors in the power supply and also the main board. Now the TV will power on and work fine for a bout 5-10 minutes and then backlights start flickering on and off until they go out completely . Confirmed TV is still powered on as I can see a faint image with a flashlight. If I power cycle it does the same thing, for around the same amount of time. Any advice on what to check? Assuming it’s still PSU issues.
Nathaniel Custer check the voltages for the LEDs on the power board. Let us know what you find on that. It is possible that this is caused by the power board (backlight Circuitry) but this back lights start flickering on and off until they go out completely” can also be caused by bad backlight strips
