When an LG’s OLED screen won’t turn on

In case this helps someone out there:

I have an LG OLED65B9‬‬ TV screen for four years. Lately, I began having trouble turning it on. Instead of powering on (from standby mode) the red LED under the screen would blink three times, and then nothing.

On the other hand, if I disconnected the screen from the wall power (220V), and waited for a few minutes, and then attempted to turn on the screen as soon as possible after connecting back to power, the screen would go on and work without any problems and for as long as needed.

When I tried to initiate Pixel Refreshing manually, the screen went to standby as expected and the red LED was on to indicate that. Two hours later, I found the LED off, the screen wouldn’t turn on, and after I did the wall power routine again to turn the screen on again, it indeed went on and complained that it failed to complete Pixel Refreshing before it was turned on.

I tried playing with several options regarding power consumption, and I upgraded webOS to the latest version as of April 2024 (05.40.20). Nothing helped.

I called service, and they replaced the power supply (which costs ~200 USD) and that fixed the problem. That’s the board to the upper left on the image below. Its part number is ‫‪EAY65170412‬‬, in case you wonder.

And by the way, the board to the upper right is the motherboard, and the thing in the middle is the screen panel controller.

(click image to enlarge)

May 19 update: A bit more than a month later, the screen works with no issues. So problem fixed for real. The LED blinks three-four times when I turn it on with the button on the screen itself. So the blinking LED is not an indication of a problem.