Samsung Syncmaster 245BW

[brisho]

Re: Samsung Syncmaster 245BW

Many thanks to all who contributed to this thread! My 245BW died last week, and a Google search led me here. I took the monitor apart yesterday, then went out today and got the necessary tools and a 5-pack of 68-ohm 1/2-watt resistors. Took a while to unsolder the old resistors (been a long time since I've used a soldering iron) and then install the new ones. Once I reassembled the monitor and plugged it in, it fired right up! Happy camper here!

[Behemot]

Re: Samsung Syncmaster 245BW

I also suggest replacing the filtering caps sooner rather than later. In mine, the bigger ones already had somewhat lower capacity.

[FLEXCopMNPD]

Re: Samsung Syncmaster 245BW

I am having the same issues. Monitor worked great then just abruptly died. I checked the resistors and they were bad. Just replaced them and the monitor still will not work. I get the faint blue light on the power button and nothing else.

I tried the test on the inverter fuse mentioned ( the little white rectangle next to the plug on the inverter board) and did not get any reading at all. Multimeter read 00.0 I am not an electrical genius so I may not have set up the meter properly. Not sure.

This thread has been a godsend.

Any other suggestions are greatly appreciated

Brian

[FLEXCopMNPD]

Re: Samsung Syncmaster 245BW

What is the procedure for testing the CM802?

Do I need to put the boards back together and turn the monitor on to test the voltage?

Thanks in advance for any help.

[budm]

Re: Samsung Syncmaster 245BW

CM802 is .018uF 630V blue rectangular cap (pulse withstanding polypropylene), check with cap meter to see if it shows really low capacitance. Your board is BN44-00173? Also make sure to remove ALL the glues. Do you have 24VDC at the output?
http://s807.photobucket.com/user/bud...tml?sort=3&o=1

[FLEXCopMNPD]

Re: Samsung Syncmaster 245BW

Bud, is a cap meter something different from a multi-meter? If it is I will have to pick one up.

And I am not sure about the 24V. Where would I test that at?

Please excuse the silly questions. I am a total noob when it comes to electronics/electricity. Although I could set the clock on my VCR when I had one

Thanks for the response. I really love this monitor and would really like to fix it.

[budm]

Re: Samsung Syncmaster 245BW

Most newer DMM of $50 or more will the function for checking the capacitance of the cap, it should say so on the box. You can check for the 24VDC at the fuse of the inverter board.

[thmoore]

Re: Samsung Syncmaster 245BW

Just wanted to issues a huge THANKS to you guys. The 3 resistor replacement did the trick (one was open, one was off spec the 3rd was good) and my 5 year old Synchmaster is back in business!

[budm]

Re: Samsung Syncmaster 245BW

@thmoore, please also make sure to remove the bad brown glues.

[Behemot]

Re: Samsung Syncmaster 245BW

I also suggest preventive replacement of those Samwha (or whichever crap) caps in there, they WILL go bad, it's just a matter of time.

[trrp]

Re: Samsung Syncmaster 245BW

My board is different than the one posted here. It is a BN44-00195A. It does not have three resistors. It has a RB808, which resists....It has a CB805 (a capacitor) which may be bad....anyone worked on this newer board?

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Hi!
I have the BN44-00195A too, and I too am looking for some answers... Can't find anything about that board, and most of all, mine is covered in yellow rosin, I can't even read the value on the capacitors...
My screen is behaving a bit differently : it works. And then, it shows a black screen, sometimes just for 1 second, and then it works again. And then, suddenly, it's black for 10 minutes (or more), and then the image comes back. Sometimes it's when I switch it on, sometimes it's after a few hours...
The power button is acting exactly like if the screen was working. Blinking when the computer is in sleep mode and the monitor still on, solid blue when it's on (even when the screen is black), and the menus and such are not appearing on the screen when I have the black screen problem.
The problem obviously comes from the screen, since I tested the cable on another monitor and it worked perfectly.
Right now, I've disassembled the power board, I tested the three resistors that looked a bit like the ones on the 245BW board, the values are correct, I cannot test the capacitors since they are covered in this solid yellow rosin that I can't get off, and I can't find any schematics of the bn44-00195A board, so there's no way I can just remove them all and replace them, since I don't know which goes where.
I was thinking about buying a new power board, but I'd like to be sure it is indeed a problem with the power board and not something else... I don't feel too confident putting everything back together (and especially soldering back the resistors I've taken out), but if there's a way I can save money and not order a power board for nothing when the problem is somewhere else, I'd rather do that ^^
Thanks a lot

[selldoor]

Re: Samsung Syncmaster 245BW

For us to help you are going to have to put back the resistors!
You HAVE to get the yellow glue off - it it going dark? it will becoming conductive and shorting components out. You also need to post pictures of your boards - see signature


EDIT Also have you read this thread
https://www.badcaps.net/forum/showth...-00195A&page=1

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Ok, resistors are back on. I need to ask my neighbor for some solder because I can't find mine (and it's past midnight here, so it will have to wait until tomorrow). I took a few pictures. I tried to take the rosin off, but it's really, really hard, and I fear it might damage the capacitors.
The stuff is yellow, and isn't darker in any place.

[selldoor]

Re: Samsung Syncmaster 245BW

Ok - maybe the glue will soften (but only slightly)with IPA isopropanol alcohol. and perhaps make a plastic pick from a toothbrush handle. It takes a lot of patience.
Did you read the thread i linked to as an edit. Maybe removing the glue will be enough
"since I tested the cable on another monitor and it worked perfectly." which cable??
Is there an inverter board in your monitor - between the power supply and the
screen. The symptoms you describe (pic goes black but power remains on may suggest
a problem with the inverter board or with the bulbs/wiring. When it goes black does it flicker at all? When it is black with it connected to a pc can you still see an image on
the screen - it will be very dark - perhaps try shining a flashlight on it at an angle.

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Yeah, I saw it, thanks! Might come in handy if I end up trying to replace the caps on the board.
There is indeed an inverter board. And no, the screen doesn't flicker at all. I can try the flashlight thing, I'll first put everything back (except maybe the back panel, no use putting everything back together to disassemble it right after) and try it.
What I meant by cable was the DVI cable from the computer. I unplugged it from the monitor and tried it on my other monitor when the screen went black. The other screen showed the image. When I put it back on the samsung, it was still black. So the DVI cable isn't the issue.
I hope I can still get it to work now that I messed with the yellow rosin and the resistors...
I'll keep you posted, I'll try that right now.

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Ok, good news is, the screen still works. I actually put it back together entirely, right now it's sitting next to me, plugged to my iPad so that I can have a constant image and be ready with my flashlight when the problem occurs. Desk is getting a little crowded right now with the three huge screens and the ipad ^^

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Hi!
Sorry for not coming back sooner. I plugged in the iPad in VGA connection, and it worked flawlessly for hours. I was pretty sure either it was fixed, either the problem was with the screen's dvi plug (which I could totally live with).
Today, I plugged the screen in dvi mode to my computer. After about 5 minutes, the screen flickered, and then went dark. I tried the flashlight thing, I can't see an image.
I tried the iPad in VGA mode again, and nothing. Black screen. Blue led is steady, not flashing. I tried changing the source (even though I can't see what I'm doing), but nothing worked.
So now, the screen is black, I left it switched on with the iPad still plugged in and I'm gonna wait to the image to maybe reappear...
Turns out, I actually did good buying a new one last week...

[newtothis]

Re: Samsung Syncmaster 245BW

Ok time to check the power outputs of the PSU when it is working and not working

[Nessdufrat]

Re: Samsung Syncmaster 245BW

How to I do that? I need to buy a new multimeter, the one I borrowed is really basic (and I gave it back anyway, so right now all I have is a soldering iron).
Also, to check it when it's working and not working, I have to disassemble the screen again? (not sure I can use it when the back panel is not screwed in, that's also why I reassembled everything)
I think I can get a new multimeter for the end of next week.

Edit : Ok, I'm pretty sure the screen is in a worse shape than before, now. It's never stayed black for that long. Also, the flickering was a really bad sign. I managed to get the flashing blue led for about one second (while it was probably searching for the source), but not the "check connecting cable" message that usually came with the flashing led. Everything stayed black.