LG L1953S doesn't power on

[Joun]

Re: LG L1953S doesn't power on

No, I've got no 5V at all.

[jetadm123]

Re: LG L1953S doesn't power on

What about the 5V output? Does it do the same thing as the 12V output?

[Joun]

Re: LG L1953S doesn't power on

Thank you for your answer..
The voltages I'm talking about are without connecting anything on power supply(just like you see it on pictures )I have soldered a plug and taking measurements but the voltages on connector are missing..
ZD301 is OK, it just has some kind of varnish on it

[jetadm123]

Re: LG L1953S doesn't power on

Check zener diode (located on bottom of board) zd301 for shorts. It looks a little discolored.

[budm]

Re: LG L1953S doesn't power on

The power supply is always on even you do not turn on the monitor, so please check the the DC voltages without turning on the monitor, see if the voltages stay on, if you turn on uinsing the switch and then you see the voltages go down, then the power supply may have gone into shutdown mode due to over current draw due to short circuits.

[Joun]

Hello
I have this LG monitor that doesn't power on.
Optically everything seems fine and I have check all mosfets,diodes, capacitors but couldn't find anything wrong..
Voltages on connector are absent with one strange expection:The moment I plug the board in I have 12volts but they are descending at a slow rate..
I mean at the begging I have 12volts,ten seconds after I have 11.5, another ten after I have 11, and so on..
I have found service manual but I had no luck with it..I'm starting to think it has a faulty PWM controller but not really sure..