Samsung Syncmaster 245B Black screen and blue Power LED

[ForceMajeure]

Re: Samsung Syncmaster 245B Black screen and blue Power LED

Sorry for doing a Necro, but I have the same problem and I have resoldered the 3x 68 ohm resistors and one was a bit high but only 10 ohm. (changed it anyway) But it didn't fix the problem.

Then I checked the inverter board and found 4 CapXon (CapXCon) and 3 of them seems like they are bulging. so here are some pics (Electro sensitive people be aware. xD)

C38 Ref.
C39
C40
Close up

I should change these for some better ones, right? Could that be the problem?

Thanks!

[vinceroger69]

Re: Samsung Syncmaster 245B Black screen and blue Power LED

yes they are bad so you need to change them all try to get some panasonic brand replacements

[ForceMajeure]

Re: Samsung Syncmaster 245B Black screen and blue Power LED

Panasonic 220 uf@ELFA

They have Rubycon, Elna, Nippon Chemi-Con and Jamicon also. Are they just as good or?

Maybe I should change some of the 8-10 caps on the PSU board while I'm at it?

[ForceMajeure]

Re: Samsung Syncmaster 245B Black screen and blue Power LED

So I changed the caps on the inverter board to Pana and replaced the 3 resistors to a big 204 Ohm one.

Any other things I should check? Maybe re-solder some of the components on the PSU as well?

[GabDr]

Re: Samsung Syncmaster 245B Black screen and blue Power LED

Hi All,
I have been following the threads on this forum for some time to try to fix my own Syncmaster 245b with blue LED but no other power. I had already changed the 3 faulty resistors a few years back but this time something else went wrong.
At first I looked at all resistors and the schematic to find out that RB801 was not right. Replacing it did not fix it. I then searched and read a lot on this forum only to find that it was probably the capacitors. I found the 18nF CM802 at 170pF (too low). Since I could not find a meter to measure all others (the one I had stopped at 100uF...) I ordered a copy of all capacitors (electrolytics) and replaced them all, plus the 18nF.
Further testing showed everyting to work fine though not the 5V and 24V... was forgetting to short S_B and PSON to simulate the ON button. Then I got the 5V and 24V!!
I am now writing this with that monitor so I wanted to thank all contributors to the forum for their great expertise and especially for taking the time to explain and give enough details that even not so expert people like myself can try and learn how to fix electronics!

[LeolaJD]

Re: Samsung Syncmaster 245B Black screen and blue Power LED

I've been reading this thread and my situation is that I replaced the 3 resistors, the monitor was working, and I thought I was done. The next day I wanted to use the monitor and it was back to being black. I took it apart and checked the CM802 and it measures 17nF. Not sure if that would be considered faulty. No capacitor looks bulged.