The solution to this is to disassemble the TV until it reaches the LED strips, verify them and replace the LEDs that may (and possibly ..) are burned, I tell you that it is a very risky job, since you must remove the lcd panel and you run the risk of breaking ... Once replaced the damaged LED (s) connect the source to the network (without the cable that goes to the mainboard is connected) and there you can see if they light all the LEDs correctly . In case of having the smd diodes damaged (which are at the beginning of each strip) you can remove them that will work the same, although these serve as protection so I recommend you put in place 24v and 12v zenner diodes. Greetings.