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Old 04-15-2012, 07:41 PM   #501
nordhaus
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Default Re: Samsung Syncmaster 245BW

All great tips from retiredcaps!

Yes, I tend to be a tool junkie, but I try to make purchases with other purposes in mind as well. My pry tools will also work well for some of my other hobbies/tasks. And I've been wanting a step up soldering iron for over a decade now (I don't even know the wattage setting of my old Radio Shack model, and I never liked using it). The Hakko was a pleasant surprise to use!

I also have 3 Samsung monitors of similar vintage, so I fully expect that at some point I'll be tearing into those too at some point.

I did forget to mention my Multimeter. Mine is an Ideal brand (includes a temperature probe function too).......I got it from Lowe's and it cost about $35. I got it because it had numerous functions, and also had a huge digital readout (I have bad eyes). I've used other Ideal products (computer networking and network line continuity testers) and have been happy.

Lowe's and Home Depot do sell the cheapie models too, but I'd be wary of those. They don't look too good.

N~
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Old 04-15-2012, 08:05 PM   #502
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Default Re: Samsung Syncmaster 245BW

Hair dryer is another good tool, same for the Compressed air duster use it upside down for cooling components.
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Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
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Old 04-16-2012, 09:16 AM   #503
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Default Re: Samsung Syncmaster 245BW

Great work nordhaus! Just out of curiousity, if you still have original cap CM802, can you please do a quick resistance test with your meter? I'd be interested to know if it opened or shorted out. Even better if you can measure capacitance on your meter. Thanks!
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Old 04-16-2012, 03:50 PM   #504
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Default Re: Samsung Syncmaster 245BW

Quote:
Originally Posted by jetadm123 View Post
Great work nordhaus! Just out of curiousity, if you still have original cap CM802, can you please do a quick resistance test with your meter? I'd be interested to know if it opened or shorted out. Even better if you can measure capacitance on your meter. Thanks!
Ugh, sorry! Once I put in the CM802 replacement and saw that the monitor suddenly began working, I tossed the old one out. Not that this is a good indicator, but on visual inspection, the old capacitor looked fine - no bulges or burn marks or other unusual marks. It was also solidly connected (I noted earlier in the thread that someone had a CM802 that was partly broken off their board).

Earlier, I did change the RM resistors as well, as one of them was definitely out of spec (I measured that one, earlier in this thread).


N~
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Old 04-20-2012, 06:05 PM   #505
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Default Re: Samsung Syncmaster 245BW

New here! I found this topic via Google and boy am I happy I found you! I had the same symptom as a few of you here... blue light, but no screen. After reading through this whole thread I was about to replace all capacitors and resisters using a kit for the 245BW which can be found on Amazon. A few said that the culprit was one bad resister, so I started with that. BOOM! My monitor works!!!!! Thanks so much!
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Old 04-20-2012, 06:07 PM   #506
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Default Re: Samsung Syncmaster 245BW

Here is the pic of the culprit!
Attached Images
File Type: jpg Samsung Syncmaster 245bw Power supply top-1 copy.jpg (415.8 KB, 98 views)
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Old 04-21-2012, 07:13 AM   #507
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Default Re: Samsung Syncmaster 245BW

Well done G Sup - you may want to consider why the resistor went bad - was it because of the caps not functioning correctly?. To extend the life of your monitor you should
think about changing the caps anyway.
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Old 04-21-2012, 08:33 AM   #508
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Default Re: Samsung Syncmaster 245BW

Great point! I will later on for sure since I have all of them. I really need to buy a better solder though. My wife uses the monitor and she doesn't use it as frequently as I use my computer, so I'll do it in the near future.
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Old 04-21-2012, 02:19 PM   #509
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Red face Re: Samsung Syncmaster 245BW

Samsung, model# 245BW (LCD Monitor)--

Symptom: no backlight, no grid; and there is no significant bias voltage going to the inverter board.

Cure: RB805 (68 ohms; open) located on power module.
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Old 04-21-2012, 08:20 PM   #510
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Default Re: Samsung Syncmaster 245BW

Quote:
Originally Posted by slidewire View Post
Samsung, model# 245BW (LCD Monitor)--

Symptom: no backlight, no grid; and there is no significant bias voltage going to the inverter board.

Cure: RB805 (68 ohms; open) located on power module.
I believe that was the resistor I was explaining?
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Old 04-29-2012, 05:49 PM   #511
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Talking Re: Samsung Syncmaster 245BW

Thank god I have found you, I was about to throw my 245BW at the trash when I did a google search and came across this post! I had the power light still on and no image, I have no welding experience and I even replaced the three fault resistors RB805-806-807! And YAY! it works. A welding kit cost me $ 15 and has three resistors for $ 1. I save hundreds of dollars cause the monitor is back in business and work flawlessly since 3 days now 24 hr a day thanks to you guys! Thank you all very much
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Old 05-27-2012, 02:13 PM   #512
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Default Re: Samsung Syncmaster 245BW

Here is a pdf scan I came across while troubleshooting my 245BW Syncmaster. I believe it ties in with Aruba's post.
Attached Files
File Type: pdf samsung_bn44-00173a_power_supply_sch.pdf (79.5 KB, 80 views)
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Old 06-10-2012, 08:44 PM   #513
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Default Re: Samsung Syncmaster 245BW

Hello all.

I just wanted to throw my thanks to all who contribute to the information herein.

Thank you very much

I have had my beloved Samsung 245b some years when it "winked" out one day weeks ago to my horror..

I dashed out and lashed out and bought a pair on 23" LG monitors (they're so light these days)... and they weren't quite the same and my challenge was to get the old 245b working again...

I googled and found some information and jumped straight in and bought a repair kit for like $25 (AUD).

I googled some more and found and read some more suggestions and thoughts here.

Well, I initially replaced those 3 resistors mentioned frequently here and she fired up and I have the caps if I feel the need.

My only advice if you will, is to replace those first, then try and get the picture as I did. It might just save you some extra work and grief.

Again, thank you to all those contributors.
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Old 07-15-2012, 12:42 PM   #514
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Default Re: Samsung Syncmaster 245BW

Thanks for all the tips on here. My monitor was making a clicking noise as mentioned in this thread. After a day or two of clicking the screen went blank but the blue power light was still on. I found the RB805 resistor bad. I replaced it and the two next to it and it fixed the problem. Hopefully it holds.
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Old 07-16-2012, 02:23 AM   #515
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Default Re: Samsung Syncmaster 245BW

Hay all I am having 2043NWX monitor and get Blue screen and no signal message pops if remove the input, also replaced most of the caps.

here is the link to thread I posted http://www.badcaps.net/forum/showthread.php?t=19613

which resistor you are taking about?

Will my monitor work if I replace it?
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Old 07-16-2012, 03:43 AM   #516
selldoor
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Default Re: Samsung Syncmaster 245BW

@rmg hrr I am having some difficulty in understanding why you have posted in this thread
you do not have a 245BW and the boards do not bear any resemblance If you read the thread there are clear pictures of the boards and the resistors?.

Unless you have anything useful to add do not post here - use your own thread.
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Old 07-20-2012, 10:47 AM   #517
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Default Re: Samsung Syncmaster 245BW

Hi guys, I am new to the forum so please bear with me if this has been discussed before.
I am trouble shooting a 245BW power supply and like many have no 5.3 V or 24V. I had one bad bulged cap (1000 uf) but replaced three of the four in that area (one 2200 uf, two 1000 uf). I also have an open circuit on on RB805 (68 ohm). I am only getting 165V on the bulk cap CP803 instead of 380v (the cap is slightly bulged).
So my questions are 1) instead of replacing the three series 68 ohm resistors why not use one 200 ohm 2 watt?
2) Has anyone experienced the bulk cap (82uf) having a low voltage like 165V? Was the issue the cap?

Thanks
Philboye
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Old 07-20-2012, 01:09 PM   #518
retiredcaps
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Default Re: Samsung Syncmaster 245BW

Quote:
Originally Posted by Philboye View Post
So my questions are 1) instead of replacing the three series 68 ohm resistors why not use one 200 ohm 2 watt?
NO, don't change the components. The 3 resistors are there for a reason. It could be acting as a voltage divider.

You can put in bigger watt resistors as others have done.

Quote:
2) Has anyone experienced the bulk cap (82uf) having a low voltage like 165V? Was the issue the cap?
The PFC won't turn on until you fix the resistors and change out the bad caps. After that, the PFC should turn on.

If you think the large filter cap is bulged, post a picture of it following instructions in my sig file below exactly.
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If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

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Old 07-20-2012, 01:13 PM   #519
jetadm123
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Default Re: Samsung Syncmaster 245BW

Quote:
Originally Posted by Philboye View Post
Hi guys, I am new to the forum so please bear with me if this has been discussed before.
I am trouble shooting a 245BW power supply and like many have no 5.3 V or 24V. I had one bad bulged cap (1000 uf) but replaced three of the four in that area (one 2200 uf, two 1000 uf). I also have an open circuit on on RB805 (68 ohm). I am only getting 165V on the bulk cap CP803 instead of 380v (the cap is slightly bulged).
So my questions are 1) instead of replacing the three series 68 ohm resistors why not use one 200 ohm 2 watt?
2) Has anyone experienced the bulk cap (82uf) having a low voltage like 165V? Was the issue the cap?

Thanks
Philboye
Since the 3 resistors are 68 ohms 1/2W each connected in series, you have a total of 204 ohms 1.5W. The 200 ohm 2W resistor should work. You just need to figure out which 2 out of the 6 holes you solder the resistor to.


You're probably seeing 165V across CP803 because the PFC circuit has not started yet. Once it starts, the voltage will increase.

Ha hah! retiredcaps beat me to it!

Last edited by jetadm123; 07-20-2012 at 01:17 PM..
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Old 07-20-2012, 02:11 PM   #520
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Default Re: Samsung Syncmaster 245BW

I'm fighting with one of these too (173A power supply).
I haven't found anything wrong, but I have replaced the most common components, since I will be keeping this monitor for myself.
Electrolytic capacitors, including the 82uF were replaced w/Pana FM/FC(except the 82uF) ones. I still have to replace the 18nF, will do it today.
I have replaced the 3x68 Ohm/2W resistors which they get very hot at the moment.
My problem is as everybody else's, black screen, power button is solid blue and no 5.3V or 24V(they are 0V). PFC stage won't start, it sits at 165V. No PS_ON voltage, only ST_BY.
I have ordered F9222L IC, just in case that I will need it. I haven't figure out the pin layout of this IC yet, but preliminary measuring doesn't look good. Measuring at three pins way to high voltages, 2x 150V and one 165V(this is probably fine). The rest of the pins are pretty much 0V.
What else can I check? I have read through many posts about these monitors, but nothing seems the same as mine. I haven't checked the BR/BQ transistor yet, but I have ordered a BR transistor just in case.
I will try using a power supply on the PS_ON pin, see if anything happens.
These monitors need the same 3.3V?
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