Samsung Syncmaster 245BW

[Nessdufrat]

Re: Samsung Syncmaster 245BW

And now it's working again (VGA connection). Because it makes total sense. *sigh*
Ok, so at least it's not dead.

[newtothis]

Re: Samsung Syncmaster 245BW

To test the voltages yes you will need the unit plugged in and powered on with access to the boards, We need to make sure all voltages that are supposed to be there are present and if not figure why not. If all voltages are there we can move onto the invertor section or backlights. Simple process of elimination.

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Ok. Can I do that with any multimeter? (I'm gonna buy one, so I might as well choose the right one)
I'll have to find a way to get the monitor on without the back panel on it (thing is, the back panel is the only thing holding the boards together, so I cannot put the monitor in any other position than face down (which is not that great when you want to see if it's working or not))

[newtothis]

Re: Samsung Syncmaster 245BW

Prop it up on 4 books or similar at the corners face down... Just and inch high or so. Gives enough room to see the screen

Yes any multimeter will do as long as the battery is good (and the meter works o'course lol)

[newtothis]

Re: Samsung Syncmaster 245BW

I will only be around for next 15 mins or so, So do what we can in that time but no doubt someone else will help guide you afterwards

[Nessdufrat]

Re: Samsung Syncmaster 245BW

Oh, I have too much work right now to take care of it and I need to buy the multimeter anyway. But I'll do the books thing, I was thinking about something like that. I'll come back here once I'm ready with my brand new multimeter and my screen open on the table
Thanks a lot for your quick replies.

(my neighbor's multimeter didn't have the farads, so I couldn't test the caps. I'm going to buy one that's a bit less lame. Also, I might need to get myself a new soldering iron, mine is 40W and takes ages to remove a single solder)

Edit : multimeter bought. I'm receiving it on Thursday at the latest.

[Oghurd]

Re: Samsung Syncmaster 245BW

I'm going to jump in here with yet another variation of the 245BW problem.

Quick background...

1) Monitor goes black one day (power button OK as usual)
2) Found this thread - replaced 2 bulging capacitors - it works !
3) Well, for 2 days - then black again (just bought another monitor at this point)
4) Revisited this problem a while later - checked the (3) 68 ohm resistors (they were reading 66/67 ohms) but replaced them anyway - it wakes up!!
5) Hmmm, not really. Here is the current situation:

• when powered ON (with no video connection) the monitor continuously cycles through White, gray, gradient-pattern(see attached image), blue, black (each screen displays about 1 second)
• there is NO menu
• other buttons have no effect
• hooking up a video input to the monitor: no change

It seems I've inadvertently put this into some kind of test-pattern loop.

Will be going back in and checking all connections.

Just needed to know if anyone has seen this / have any ideas.

Thanks,

[Oghurd]

Re: Samsung Syncmaster 245BW

Last night I did go back to check connections...didn't see anything wrong but re-seated all connections - and it worked! (still no idea what caused the test pattern cycling).

Unfortunately, after using it for a few hours last night with no problems, switching it on this morning I am back to nothing - not even a power light this time. Pretty aggravating.

[selldoor]

Re: Samsung Syncmaster 245BW

Did you remove all the glue?

[Oghurd]

Re: Samsung Syncmaster 245BW

Good point, I did not remove all glue from everywhere. Will do so this evening when I open it back up to poke around some more.

Does anyone know if the complete lack of power (to the blue 'on' button) points to a particular problem component? I expect this is a possibility considering this seems to be an intermittent problem.

[Behemot]

Re: Samsung Syncmaster 245BW

In such case most likely the stand-by supply is bad.

[Oghurd]

Re: Samsung Syncmaster 245BW

In such case most likely the stand-by supply is bad.

OK, is the stand-by supply something that can be fixed easily? Or is it some type of integrated component?

... also, where exactly is it?

(Just wondering at which point I should just give up and move along)

Thanks,

[Behemot]

Re: Samsung Syncmaster 245BW

It's complete circuit, it has common part of primary side with the main power supply but separate switcher, transformer and secondary side. Its the supply with operates continuously, feeding basic signal circuitry which can than turn on the main supply and start processing/displaying image.

[viziks]

Re: Samsung Syncmaster 245BW

From the intermittent nature of problem described by you and going into test / service mode I have a suspicion that your keypad assembly may have leaky switches which would account for this behaviour.
Check the voltages and if all seem ok suspect the operation keypad.

[dukecem]

Re: Samsung Syncmaster 245BW

Hi folks,
This is my first time to post a message. I hope this is OK to jump in here with my strange symptom concerning my Samsung 245BW which has the BN44-00173 power supply board in it. Here is what has happened so far:

It has an intermittent problem with coming on when the computer is booted up. It "sees" the computer because the blue light goes from flashing to a steady glow, but the screen does not come on. I have found that pressing to power button off then back on will sometimes turn the screen on. If that does not work, flipping off the master power switch on the back, then back on will sometimes get it to come up. And, if that doesn't work, all you can do is leave it and come back later or tomorrow and try again. I've tried this monitor on three different computers and it has the same symptom on all of them.

Here is what I have checked so far:
I've read the blogs about changing out all the caps and the three 67 ohm resistors on the power supply board BN44-00173. I checked and the two 10 volt 1000 microfarad caps, located at the bottom center of the board, had a slight bulge on their tops, so I replaced them with new ones from an EBay company selling the 14 caps and 3 resistors repair kit. The rest of the caps look just fine and the three resistors look like new and they, all three, check out at about 67 to 68 ohms. After replacing the two questionable caps with known good ones, I then had no blue light in the power button on the front panel.

Does anyone have any idea why two good caps replacing questionable caps would cause a "no power" to the blue light on the power button? I replaced with a second pair of new caps; still no blue light. Oh, I put the two old caps back where they were and, low and behold, I have my blue light back! Go figure....makes no sense to me.

The monitor is up and working fine right now while I am typing this message, and has good picture and good color. When it is on, like now, it never flickers nor shuts down unexpectedly. Its problem is this intermittent problem of getting it to bring up the screen when you need to use it, which makes it very unreliable. Since it works great, when it works, it doesn't sound like it has a serious problem. I just don't have any idea where or what to check; or what to replace at this point.

If anyone has seen this symptom before, I would so appreciate whatever suggestions you have to go about solving this problem. It is far too nice a monitor to get rid of it without a good try at fixing it.

Thanks, Duke

[joshnz]

Re: Samsung Syncmaster 245BW

Interesting.
My samsung monitors have had two issues,
bad capacitors and inverter transormers.

When you power light is solid on shine a bright light on screen and see if you can picture use different angles.

new capacitors maybe fake or installed backwards.

[dukecem]

Re: Samsung Syncmaster 245BW

Ok, with the blue light on solid I tried the bright light and there is nothing, no picture; just a black screen. The new caps from EBay company and the second new pair from Radio Shack were both installed with great care making sure the negative terminals of each pair were installed the same way that the original pair were installed with the negative band over the black hole on the board. Since I got no blue light with either pair of new caps, I put the original old pair of caps back on the board and now I have my blue light back. Again....a total mystery to me!

How would you know if a capacitor is fake? I would think the caps from Radio Shack would be the real thing, since Radio Shack is a legitimate company......but, I just don't know how to tell a real one from a fake one. I just figured the EBay company selling all the 14 caps and the 3 resistors kit specifically for this Samsung SyncMaster 245BW would know what type caps were required. I may have gotten ripped, who knows. But he does have a 99.5% positive feedback from over 14,000 sales. It seems like almost all other buyers were happy.

If this unit requires some special type caps.....I just don't know what to ask for to make sure I'm getting the right ones. If you know what is required exactly, please let me know how and what to order.

Thanks for replying and helping me, Duke

[joshnz]

Re: Samsung Syncmaster 245BW

Ok, with the blue light on solid I tried the bright light and there is nothing, no picture; just a black screen. The new caps from EBay company and the second new pair from Radio Shack were both installed with great care making sure the negative terminals of each pair were installed the same way that the original pair were installed with the negative band over the black hole on the board. Since I got no blue light with either pair of new caps, I put the original old pair of caps back on the board and now I have my blue light back. Again....a total mystery to me!

How would you know if a capacitor is fake? I would think the caps from Radio Shack would be the real thing, since Radio Shack is a legitimate company......but, I just don't know how to tell a real one from a fake one. I just figured the EBay company selling all the 14 caps and the 3 resistors kit specifically for this Samsung SyncMaster 245BW would know what type caps were required. I may have gotten ripped, who knows. But he does have a 99.5% positive feedback from over 14,000 sales. It seems like almost all other buyers were happy.

If this unit requires some special type caps.....I just don't know what to ask for to make sure I'm getting the right ones. If you know what is required exactly, please let me know how and what to order.

Thanks for replying and helping me, Duke

Hi duke I suggest you make a new thread in this forum.
https://www.badcaps.net/forum/newthr...newthread&f=30
and we will go from there.

[Nanoda]

Re: Samsung Syncmaster 245BW

I'd like to add a data point (and thank the people on the first page from 2011 for the tip) as replacing the 3 x 68Ω resistors got my monitor working right away! (Black screen, not a backlight problem, lit LED)

[warnesj]

Re: Samsung Syncmaster 245BW

I'd also like to thank everyone here. I also replaced the 3 68Ω resistors in the power supply and it fixed my problem. Wonderful information!