Samsung Syncmaster 245BW

[trossi]

I have what seems a common problem. I have no picture at all but the power LED lights. The failure was sudden. The monitor worked perfectly then the next time I powered it on, I had no picture. Pushing the menu button has no visible effect. I connected it to a second computer to confirm that it was the monitor and not the PC.

I assume the inverter has failed but don't know how to test that hypothesis. I have disassembled the monitor and did not see any bulging capacitors.

Can anyone suggest next steps? I have a multimeter but am inexperienced in its use. If you suggest testing components please explain the testing procedure, e.g. power on/power off, where to place the probes, etc..

Thanks very much,

Tom

[PlainBill]

Re: Samsung Syncmaster 245BW

I have what seems a common problem. I have no picture at all but the power LED lights. The failure was sudden. The monitor worked perfectly then the next time I powered it on, I had no picture. Pushing the menu button has no visible effect. I connected it to a second computer to confirm that it was the monitor and not the PC.

I assume the inverter has failed but don't know how to test that hypothesis. I have disassembled the monitor and did not see any bulging capacitors.

Can anyone suggest next steps? I have a multimeter but am inexperienced in its use. If you suggest testing components please explain the testing procedure, e.g. power on/power off, where to place the probes, etc..

Thanks very much,

Tom

Often the same model monitor has several variations. There is a simple test you can try - hook the monitor up to a computer, turn them both on, and see if you can see anything by shining a flashlight on the screen. If that works, please attach a picture of the entire monitor and another of the inverter using 'Manage Attachments' - below the text entry area.

PlainBill

[trossi]

Re: Samsung Syncmaster 245BW

No image visible using flashlight.

[PlainBill]

Re: Samsung Syncmaster 245BW

No image visible using flashlight.

What happens if you press the Power button? Does the power led go on and off?

The bottom line on this is sooner or later you are going to have to open the monitor up and attach pictures of the power supply. There are a number of possibilities, but one is a shorted driver caused a fuse to blow. Pictures should be close to - but less than - 2000 pixels x 2000 pixels. I want one of the top and another of the bottom of the power supply. Attach them using 'Manage Attachments' below the text entry area.

PlainBill

[trossi]

Re: Samsung Syncmaster 245BW

As I mentioned in the original post, the power on LED does turn on when the monitor is turned on.

You'll see two white fuses side by side in the upper left corner of the front side photo. Unfortunately they aren't transparent and thus can't determine by looking whether they are defective.

Hopefully the photos are adequate. My digital SLR got doused by a wave and died. These were shot with the 8 megapixel camera on my phone at the highest quality setting.

[jetadm123]

Re: Samsung Syncmaster 245BW

A common failure on your model board are resistors RB805, RB806 and RB807 located in the middle at the very bottom of your board. They each should read 68 ohms.

[trossi]

Re: Samsung Syncmaster 245BW

Good call. 805 reads 400k. The others read 67 or 68.

[PlainBill]

Re: Samsung Syncmaster 245BW

As I mentioned in the original post, the power on LED does turn on when the monitor is turned on.

You'll see two white fuses side by side in the upper left corner of the front side photo. Unfortunately they aren't transparent and thus can't determine by looking whether they are defective.

Hopefully the photos are adequate. My digital SLR got doused by a wave and died. These were shot with the 8 megapixel camera on my phone at the highest quality setting.

Excellent quality pictures. And glad to see you have already identified the problem.

PlainBill

[trossi]

Re: Samsung Syncmaster 245BW

How do I specify the part? Just ask for a 68 ohm resistor?

[trossi]

Re: Samsung Syncmaster 245BW

I replaced the bad resistor and it now passes the flashlight test but no backlighting.

[PlainBill]

Re: Samsung Syncmaster 245BW

I replaced the bad resistor and it now passes the flashlight test but no backlighting.

Well, you should know the drill by now.

The power supply sends 24V and two signals - INV_ON and BRI to the inverter. INV_ON (or it might be called ON/OFF, etc) should be above 3V. Make sure the fuse (fuses?) are good on the inverter.

And of course, a picture will help.

PlainBill

[jetadm123]

Re: Samsung Syncmaster 245BW

Yes, please post a photo of the inverter.

[trossi]

Re: Samsung Syncmaster 245BW

I've attached the inverter board photo. How do I perform these tests?

From another thread I know that the inverter board fuse is the small white rectangle just left of the plug from the power supply. The other fuses are on the power supply in a previous photo.

[trossi]

Re: Samsung Syncmaster 245BW

Nevermind. After I took the inverter photo, I examined the plug from the power supply to try to figure out which lines to test and noticed the plug slightly askew. I clicked it into place and the monitor works.

The resister -- $1.19 for five at Radio Shack -- was the only problem.

Thanks to you both for your help.

Tom

[Gary Indiana]

Samsung Syncmaster 245BW black screen

A common failure on your model board are resistors RB805, RB806 and RB807 located in the middle at the very bottom of your board. They each should read 68 ohms.

Thank you jetadm123 for sharing the knowledge! You, bro, fixed my monitor.

Long story short:
My 4-year old 245BW died prematurely. Power button blue light works and reacts but screen is pitch dark with no sign of life whatsoever even under a flashlight. It worked like a champ till now. So I thought this might be a common problem, and besides that: it's just too good a monitor and too new to toss away.

I found a lot of pure nonsense posted on yahoo answers and on fixya, all terrible garbage from people who never held a screwdriver in their life, so it seemed. And finally I found this great forum with this problem professionaly solved right away!

Let me share some of my experiences as it may help another person.

First of all, soldering skills is a MUST. This is not a job for a first-timer.

Q: What you need besides broken 245BW? A: Soldering iron, solder pump (sucker), a pack of five 68 Ohm 0.5 Watt resistors for $1.19 at Radio Shack, a couple of flat screwdrivers for opening the case, and philips #2.

To open the case first remove 4 black screws holding the stand.



Then use flat screwdrivers to unclip plastic tabs around the back cover. This is hard, although the plastic is tough and doesn't break easily. This picture below shows where the rectangular holes for the tabs are located. I put light-colored masking tape under to make them better visible.



Unplug connectors on both sides of the inverter board. See the 2 pictures below. Be careful not to break any parts of the plugs.





Unplug the tiny cable on the right hand side. Press down its little plastic tab to release it.



Remove 4 screws holding the power supply board and flip it over.





Locate three brown/red 68 ohm resistors in the center bottom part of the board. In my monitor, RB805 was opened. They are glued all 3 together with some horrible brown stuff. I think it's best to replace all three resistors once you open the case.





All three old resistors removed.



New resistors soldered in place.



Monitors works like new!

[ROMAD]

Re: Samsung Syncmaster 245BW

Not to thread-necro, but I just wanted to say thanks for this thread. I was able to diagnose & fix my 245BW in less than 2 hours. A short trip to Radio Shack later and I had the resistors, plus a new soldering iron :P . Excellent instructions!

[DetectiveBasil]

Re: Samsung Syncmaster 245BW

Romad: I appreciate the thread-necromancy you pulled here, I just received this same monitor from my aunt with the same exact problem.

I haven't done the flashlight trick yet, hopefully it's the same simple fix as this one though.

This coming week is finals week for me, so I won't be able to open it up and have some fun just yet.

First of all, soldering skills is a MUST. This is not a job for a first-timer.

I've had some soldering experience in a Computer Repair & Assembly class I took, though I admit that was a year and a half ago.

I don't have a great soldering station, in fact the one I do have was part of an electronics tool kit a family member bought me for this last Christmas. Will that do or do I need drop $$ to do this?

Thanks!

Edit: Now that I think about it, I don't have any sort of a tester. What kind would I need to accomplish this fix?

[selldoor]

Re: Samsung Syncmaster 245BW

Welcome to the forum- It probably best if you dont even start this until you finish your exams. - Good Luck with them.

IF the fix is as above you wont actually need a meter/tester you may as well just buy the resistors for a couple of dollars.

You will need a small pack of solder -thin stuff with lead in and with flux in
is ok for this. You will also need de-solder braid (soldermop) to remove the old solder from the board.

If the fault turns out to not be as above then yes you will need a multimeter. It then depends on whether this is a one off fix or the start of an interest in electronic repair and of course how much you want to lay out. If you look and see what you can buy/ afford then ask again on here
saying how much you want to spend someone will advise further.
You can also search on the forums to see what has been suggested before.- The search in the bar at the top is very useful.


We can help a lot more if you please post good clear pictures of the whole chassis, and then pictures of each board, front and back and close up of connectors, (max resolution 2000x2000 and 2MB) using the manage attachments button, which is found by clicking "go advanced" under quick reply.

Please do not post inline and offsite as they slow down the loading of pages.

Examples of what is needed
https://www.badcaps.net/forum/attach...1&d=1290283049

https://www.badcaps.net/forum/attach...7&d=1280167246

[risim]

Re: Samsung Syncmaster 245BW

Just wanted to thank everyone who has contributed to this thread. I bought a 245bw second hand two days ago and got it home to discover the symptoms described here. Using your guides I replaced the faulty resistor and now have a working, beautiful 1920x1200 monitor to show for it.

Thanks to everyone.

[budm]

Re: Samsung Syncmaster 245BW

Great! make sure to remove ALL the glue also.