Hello, this tv customer said it will work for sometime about 2hrs then backlight will start going off, so i opened to the point of backlight then i powered on the tv to see things my self, then i noticed the tv has two backlight at each edge, each of the unit has 4 set plus 4 extral in all a number of 60 diode bulbs, sometime i will see half of 30 go off on each side, when i put off the set and power again it will light on, i have tested each bulb with DMM and they all light, sometime one complete side will go off. and sometime it will stay on as if it has no problem . here is the LED driver board , when i tested the bulbs one after the other, with Dmm i noticed some will light and stay on while some light and drop, but if i use Analog MM all the bulbs will light and stay on

 

I ended up replacing my TV with 4K 51" for about $300. Prior to that I replaced a $75 board and a TRIAC which burned out again.