LG OLED 55B7V does not start

[PowerAmpFreak]

LG OLED 55B7V respond to power-on button, PSU goes on for a second then stops.
No sign of picture nor sound.
Any advice?

The PSU has two main outputs. One +12V and one +24V. The 12V supply is running for like 5 seconds, and the +24V output shuts off after a second.
If disconnecting the loads, the voltages stays on both of them, until the diagnostics turns off the PSU.

Sourcing the +24V continously from external PSU does not change behaviour.

Thanks in advance!

[Diah]

Re: LG OLED 55B7V does not start

Sourcing the +24V continously from external PSU does not change behaviour.

Thanks in advance!

using external source for 24V panel driver boards a big mistake..
put every things as original in place .. only the socket 24V from psu to T-CON driver boards disconnect it from PSU side and turn on.. let yours eyes on the Audio optic port on MB if it lit red and for how long.

[PowerAmpFreak]

Re: LG OLED 55B7V does not start

When I turn on the set without the 24V connector from PSU side connected, the optical port stays on for 10 seconds.

EDIT: Found the issue - a shorted ceramic 10uF cap on the T-CON board. Now it works!

[dskall]

Re: LG OLED 55B7V does not start

Good job. Can you put down location of bad cap? The question will be asked.

[PowerAmpFreak]

Re: LG OLED 55B7V does not start

I started off by checking the youtube vid below:
https://www.youtube.com/watch?v=WHjJpT77jpY

14:08 in the vid he probes resistance across a voltage converter MLCC bank.
In my case I could see a small crack in the cap so I did not need to go for current injection and thermal camera method.

Also attach a screenshot of area from vid.

[Diah]

Re: LG OLED 55B7V does not start

common man... from his hand color and the T-CON under his hand... its not OLED and Asian famous with fake.. they caused fault and then they cliam repair or issue found LOL