Samsung 205BW bad connection problem?

[zoria]

Thanks for a great forum. All my google searches on my monitor leads to this forum. I already searched and my problem seems to be a little different.

I bought the Samsung 205BW from staples new. It shows random problems such as.

1, sometimes pressing the menu button will not bring up the menu on screen or if it does, the menu will all be corrupted showing some texts that I do not understand.

2, sometimes, the lcd will be totally dead but let it sitting a few hours or days will bring it back to life.

3, VGA port seems to got poor connection problem and the color will become totally green or red. The DVI port seems to be working and if the LCD is back to life, it can stay on for weeks or even a few months before it is totally dead and needs to be un-powered (disconnect the power cord) for a few hours or days.

4, The unit is very slow and it takes about 3 to 6 seconds to show anything after I press the power button.

Could this also be a Cap problem? I am pretty handy and have fixed some motherboard by replacing some bad parts but really do not know what is wrong with this unit.

Thanks everybody.

[retiredcaps]

Re: Samsung 205BW bad connection problem?

Could this also be a Cap problem?

Yes, you could have bad caps.

1) Open it up and post pictures so we can make suggestions. Post clear focused pictures after reading

https://www.badcaps.net/forum/showthread.php?t=1868

2) Please do not post pictures inline.

3) Take your boards to a window on a sunny day, turn flash off, and use macro mode. Take a top down view of all your boards (front and back). Make sure the photo is legible so that we can read the PCB printing clearly. A shutter speed of 1/125 or faster will produce nice clear focus pictures. Try to get a photo that is 2000x2000 resolution or as close as possible.

Here is an example of the pictures we want.

https://www.badcaps.net/forum/showpo...94&postcount=1

[zoria]

Re: Samsung 205BW bad connection problem?

Thank you, will do it asap.

[zoria]

Re: Samsung 205BW bad connection problem?

I think I just be a victim of the Caps as well. I uploaded 3 pictures here. my eyes tell me that C328,C327, C265 might be bad. What a surprise.

Picture 4 and 5 are close-ups.

C328 and C327 are the two big ones. I see 1000uf 25V.
C265 is the tiny one besides the two big ones. It says 475uf 25V.

[retiredcaps]

Re: Samsung 205BW bad connection problem?

my eyes tell me that C328,C327, C265 might be bad.

I count 7 caps (including the big one on its side).

Since 3 out of 7 are bad, it is not a stretch to think they all may be bad. The exception might be the big one. It rarely, but not never, fails.

With an almost 50% cap failure rate, most here will recommend that you replace them ALL (except the big one). Caps are cheap so replace them all.

If you live in the USA, follow PlainBill's instructions to choose Panasonic low ESR FM or FC caps.

https://www.badcaps.net/forum/showpo...33&postcount=2

PS. Great focused pics.

[Wrog]

Re: Samsung 205BW bad connection problem?

Definitely. Replace them all while you have it open, not just the ones that appear to be bad (including that small one at the top next to the heatsink). Skip the large one on its side.

[retiredcaps]

Re: Samsung 205BW bad connection problem?

I bought the Samsung 205BW from staples new.

The date codes on the Capxon caps looke like 0634.

06 = 2006
34 = 34th week into the year

So it looks like this monitor lasted 4 years before the caps died.

[zoria]

Re: Samsung 205BW bad connection problem?

Thank you, retiredcaps and Wrog. You sure got eagle eyes. The huge cap actually says 060916. I see 0638 on the yellow rectangle SPI thing. So that means the 34th week of 2006?

I bought the monitor at the end of 2006 and it began this problem in mid 2008 when it was still under warranty. As the problem was very random, I didnot call Samsung.

Great idea to replace them all. Now need to read PlainBill's post. Thanks again.

By the way, anybody know if there is a shop near Boston. I know everybody recommends Digi-Key but if there is a local shop, maybe I can contribute to the local economy?

Edit: I see the four big ones are all rated 1000uf and 25V. Why two are bigger than the other two near the smaller one? A little confused.

[retiredcaps]

Re: Samsung 205BW bad connection problem?

You sure got eagle eyes.

I only wish.

By the way, anybody know if there is a shop near Boston. I know everybody recommends Digi-Key but if there is a local shop, maybe I can contribute to the local economy?

Edit: I see the four big ones are all rated 1000uf and 25V. Why two are bigger than the other two near the smaller one? A little confused.

I don't know about Boston, but just make sure the local shop carries one of the the recommended brand low ESR caps at

https://www.badcaps.net/forum/showthread.php?t=2280

Manufacturers can make caps of the same uF and voltage in different "series". Each series has different ripple, ESR, lifetime, temp, etc characteristics. Each series can range in size (height, diameter) depending on the application.

[zoria]

Re: Samsung 205BW bad connection problem?

Manufacturers can make caps of the same uF and voltage in different "series". Each series has different ripple, ESR, lifetime, temp, etc characteristics. Each series can range in size (height, diameter) depending on the application.

Thank you. I now understand. I just checked for the 1000uf and 25V Cap, they only have one size anyway. So I went ahead and placed the order. Only 5 bucks for all Caps. Not worthwhile to contribute to the local economy.

[MBAJACE]

Re: Samsung 205BW bad connection problem?

I have the 205BW with identical problems. The Screen functions perfectly.
I replaced the same 3 caps you identified and it made the monitor power cycle faster than before. 1.5sec flash. Powerlight blinking. I unhooked the ccfls and screen works but is black.

I think the problem is the bulbs, I have an external ccfl inverter and have 4X 15'' ccfls and need 6X 20'' ccfls but can't find. Screen works perfectly just a little spotty.

With the external inverter I could power up ccfls ( the 20'' stock ) 3/4 to full length but pretty sure I was underpowered by 2 volts input. I will get the output. Ayone know the bulb specks?

The fuse looks good

[zoria]

Re: Samsung 205BW bad connection problem?

Have you tried to replace all the caps? That might help.

Well, the bulbs might be a problem as well. I notice that my screen is about 50 to 70% of the original brightness. But I am using it as a back up screen anyway so I do not really care.

[zoria]

Re: Samsung 205BW bad connection problem?

Update: My caps arrived and I have replaced all six. I replaced them all. Now there is no video. Did I screw the monitor? I have soldering for over 15 years (amateur) and I was really careful. Now neither VGA or DVI works. The screen will light up immediately upon pressing the power button but just plain white. Pressing the menu button does nothing either, no English, German or anything. Anybody experienced this problem?

I did pay attention the polarity. It seems the Negative end have to match the negative end on the board.

[alexanna]

Re: Samsung 205BW bad connection problem?

Check that you installed the ribbon cable correctly into the LCD panel
Al.

[zoria]

Re: Samsung 205BW bad connection problem?

Good idea. Sounds reasonable. I will double check, maybe reseat the video cable. Will report back.

[alexanna]

Re: Samsung 205BW bad connection problem?

I should have said upside down into the LCD
Ben there done that
Al.

[zoria]

Re: Samsung 205BW bad connection problem?

Alexanna, thank you very much. The video cable is indeed a little loose. I guess when I plug it in, I accidentally pulled it a little bit. It is just out about .5mm.

Anyway, it works fine now. The LCD is actually brighter than before. Almost 100% brightness as when it was purchased. Before the re-cap, it was definitely less than 50% or even very dark sometime. Glad it works now.

Thanks all the members here.

[alexanna]

Re: Samsung 205BW bad connection problem?

Alexanna, thank you very much. The video cable is indeed a little loose. I guess when I plug it in, I accidentally pulled it a little bit. It is just out about .5mm.

Anyway, it works fine now. The LCD is actually brighter than before. Almost 100% brightness as when it was purchased. Before the re-cap, it was definitely less than 50% or even very dark sometime. Glad it works now.

Thanks all the members here.

I should write a book about all the things I've done wrong on monitors
Well I learn, and most important remember those things and try not to do them again.
Al.