LG Flatron W2353V no power on, nothing.

[conrado.g]

Hi folks,
This is my first post. Richard over at YT Learn Electronics Repair recommended this forum in one of his videos. I am learning electronic repair now in my thirties.

I have an LG Flatron W2353V that doesn't power on. It just stopped working from one day to the next. No lights, no nothing, and I don't know how to test the keypad since it doesn't have buttons, just a touch keypad. I took out the power supply board, and am attaching pictures. Some of the capacitors are bulged. I have a multimeter and have tested voltage at several places:

Capacitors:
C101: 309V (That's the big one)
C203: 24.2V
C204: 5.1V
C205: 5.1V
C207: 24.1V
C212: 5.1V
C301: 24.1V

Plugs:
The ribbon plug has voltages as labeled: 5V, 22V and ground. Only, the 22V pins mark about 24V.

The other two-wire white plugs (P401, P402, P403 and P404) don't mark any voltage at all across their pins.

And that is as far as I know what to measure. Is this board fine, and the problem is in the control board? or is there something else that I need to measure to diagnose here?

[momaka]

Re: LG Flatron W2353V no power on, nothing.

Hi Conrado, welcome to BCN!

First replace the bulged capacitors, then we can continue from there.

The voltages might appear OK, but the bulged capacitors means they are failed and not filtering noise properly. When there is too much noise, the logic board may refuse to work properly. So until the capacitors are replaced, there's no point to try to look for any other issues. There's a good chance the monitor will work fine after this, though... unless the bad caps took out a regulator on the logic board (it's possible, but not that common.)

So that's your homework for now: replace the caps.
Make sure the replacements are good low impedance / low ESR type, and preferably Japanese brands. For testing purposes, though, even GP caps might be OK, if that's easier to find where you live.

[conrado.g]

Re: LG Flatron W2353V no power on, nothing.

Hi Momaka, thanks! I will replace the caps, when I can get them, and then I will update again. It will be at least several days for me to get them. Cheers!