[Solved] LG 50LB650V-ZN - the picture is flashing, the voice is, are the LEDs down?

Hello
Symptoms similar to the subject https://www.elektroda.pl/rtvforum/topic3372437.html, a few months ago I noticed two barely visible darker spots on the matrix, and today the TV has been working for about 40 minutes and suddenly the image began to flash (as if it appears and disappears immediately). Were the LEDs down? I have recorded a short video of what it looks like, but I don't know if it will work after placing it on the website.

Thank you

Quick update: TV turned on itself and has been working perfect for 10 minutes. Can anyone explain to me what's going on? Unfortunately, I scared - after 15 minutes the picture disappeared again and only blinks.
Next update:
if I turn the TV off and connect it after a few hours (say 12), when I turn it on it works fine for about 30-40 minutes, after that time it starts blinking again.

I put pictures of the disc and markings on the matrix.

Disc designation:
PCB: EAX65423801 (2.1) REV2.0 2013.12.30
Matrix:
LG LC500DUH (FG) (P2)

I did 42LB so much that the matrix was of the HC420DUN type 6V diode. Checking the diodes in the 50-inch matrix is a real challenge. Of course, before that the power supply.

I had a similar symptom where the image flashes in order in the 50LB650V model on a pcb: eax65423801 the reason was led strips 3 strips are connected in series separately to the board, which were damaged can be connected to the led + pin, led - from the j52 jumper side a 40-60w light bulb , if the other 2 strips are OK, which are also connected in series to the second led + led - this part of the matrix will be illuminated without blinking, if the power supply is OK.

marekstoczynski wrote:

I had a similar symptom where the image flashes in order in the 50LB650V model on a pcb: eax65423801 the reason was led strips 3 strips are connected in series separately to the board, which were damaged can be connected to the led + pin, led - from the j52 jumper side a 40-60w light bulb , if the other 2 strips are OK, which are also connected in series to the second led + led - this part of the matrix will be illuminated without blinking, if the power supply is OK.

The TV went to repair and new LED strips were installed because in previous ones almost all bulbs were burned out.

I close the topic

marekstoczynski wrote:

I had a similar symptom where the image flashes in order in the 50LB650V model on a pcb: eax65423801 the reason was led strips 3 strips are connected in series separately to the board, which were damaged can be connected to the led + pin, led - from the j52 jumper side a 40-60w light bulb , if the other 2 strips are OK, which are also connected in series to the second led + led - this part of the matrix will be illuminated without blinking, if the power supply is OK.

The TV went to repair and new LED strips were installed because in previous ones almost all bulbs were burned out.

I close the topic

Added after 1 [minutes]:

The TV went to the RTV / TV service where new LED strips were installed.