Unstable Power System or Damaged LEDs? LG 50LB650V TV Backlight Issue and EAX65423801 (2.0) Module

In the TV set, the matrix backlight turns on and off periodically every 1s, and at the same time the sound is correct and the picture is also correct.
The voltage of 3.5V, 12V and 24V on the EAX65423801 (2.0) rev.1.0 module is completely correct, the power supply voltage for the LEDs is about 140V (it floats between 135 and 142).
My question is whether this is due to the unstable operation of the power system or damage to the LEDs in the backlight. This knowledge is so important that it can save me from disassembling the matrix.
Maybe someone has a diagram of the power supply board?

Quote:

LED supply voltage at the level of about 140V (it floats between 135 and 142).

Indicates the LED lines (strings)?
* Measurements on .. regarding common mass> enter (excl. LED line)

Quote:

LED_OUT1 (-), LED_OUT1 (+), LED_OUT2 (-), LED_OUT2 (+)

What matrix?
What layouts in this ver. PSU ... (2.0) rev.1.0?

This PSU on the PCB: EAX65423801 (2.0) rev1.0 (LGP474950-14PL2) used 47LB561V (LC470DUH-FGA2)
Such an interesting movie with TV Led LG 39LN5400 (MAP3202) Link_ MAP3202


LGP474950-14PL2
OUT: 3.5V / 1.8A; 12V / 1.4A; 24V / 0.8A
LED 47 ": 117V / 230mA
LED 49 ": 113V / 205mA - 170V / 205mA
50 "LED: 113V / 215mA - 170V / 215mA
LED 55 ": 145V / 230mA - 218V / 230mA
60 "LED: 205V / 160mA
___________________
PSU on EAX65423801 (2.1) Rev2.0 with 47LB561V (LC470DUE matrix)
- LED BL0202B driver, 2-ch. driver, datasheet in app.
* search on aliexpress as (BL0202B-IC-LCD-power-management-chip)
- usually it rains (slight heating symptom)

Matrix T500HVJ03.0, LED driver on BL0202B board. The voltage at the outputs of the leds are 135-142 when connected, while when the leds are disconnected, the first output is 162-172 and the second is 135-142; measurements relative to common mass.
I do not know anymore whether to disassemble the matrix and make sure that any of the diodes is shorted and therefore protect turns on, or to look for BL0202B.

Is this driver system heating?
* like No ... this
Rather, it looks like led lines.

This driver is slightly warm, but it is probably caused by normal operation, the warmth is only slightly perceptible. However, I will probably have to disassemble the matrix.

Disassemble the matrix and see if all the LEDs are on
- of course with the difference in lighting, because the voltage is "unstable)

If so (they are all lit), change the layout!

The VCC supply voltage of the BL0202B chip, stable (not pusing)?
Read the datasheet and the role of the pins responsible for OVP, pin 13/17 and the start operation
Link_ by Sanken

I will join. I have the same symptom, the backlight turns on and off. Except that the tensions are as follows; 170-179V and 137-147V without LEDs relative to common ground. However, with load: 194-214V and 91-94V. The driver's power supply is stable, the driver does not heat up. So we have that the voltage under load increases on one branch and on the other it drops quite significantly. Driver?

Disassemble the matrix, a few diodes will be burned, you will replace the diodes or strips themselves and it will be ok, that's what I did. It would be best to replace the entire backlight, but the cost in the north is PLN 300 net
With one or two lit LEDs, the backlight is still on, with a larger number it does not; the backlight flashes.
In my case, the TV fell 1 month after the warranty.

Ok! Thanks.
By the way, it was said that LEDs would last forever. And they last shorter than fluorescent lamps, one big G.

In older TV sets and maybe better LEDs were on aluminum strips, so they dissipated heat a little better, now they are on laminate ... costs.
I close the topic.