Samsung Syncmaster 225BW

[michaelahess]

Re: Samsung Syncmaster 225BW

Just over 7 months ago I used this site to get caps for my 225BW and got the monitor back up and running. I used the following caps:

United Chem:

EKY-250ELL331MJC5S
ELXY250ELL821MK20S

Nichicon:

UTT1H470MPD

The repair went well and things have worked fine until today, the monitor shut off. Now it's doing the same thing, turn on for a few seconds, then display goes off and blue light blinks.

Were these bad cap choices? Any other possible causes? I looked at the board and nothing is bulging or even hot. The only cap not replaced was the big one which is capxon.

I've got pictures but they aren't telling and look the same as everyone else's with the rev0.2 board.

Thanks for any help guys!

[retiredcaps]

Re: Samsung Syncmaster 225BW

United Chem:

EKY-250ELL331MJC5S
ELXY250ELL821MK20S

KY and LXY are low ESR caps so they should be good.

Nichicon:

UTT1H470MPD

I don't know about the Nichicon and I can't tell from digikey's description.

Now it's doing the same thing, turn on for a few seconds, then display goes off and blue light blinks.

I've got pictures but they aren't telling and look the same as everyone else's with the rev0.2 board.

1) Clear focused pictures of YOUR board help. Some members can spot a problem just by looking at the board.

Follow the instructions in my sig file to upload your pictures using the manage attachments function.

2) Hookup a working computer showing your favourite wallpaper. Connect your lcd, can you see the wallpaper if you shine a flashlight on it? If yes, you have 2 seconds to black. Possible causes can be

a) bad caps
b) bad ccfls and/or ccfl wiring
c) bad inverter transformer
d) bad ccfl sense circuitry

All are discussed in more detail starting with post #13 and #14 at

https://www.badcaps.net/forum/showthread.php?t=10419

[michaelahess]

Re: Samsung Syncmaster 225BW

Here's the photos. I tried the flashlight trick and can see the screen. So other than bad new caps I'd guess CCFL from what I read. There is no buzzing or humming that i can discern.

[retiredcaps]

Re: Samsung Syncmaster 225BW

With power off and lcd unplugged, measure the resistance of secondary inverter transformer pins (T301 and T302). They are the pins "going into" the blue caps.

Report both ohms measurement.

[michaelahess]

Re: Samsung Syncmaster 225BW

1.098k and 1.097k if I understand your meaning. That's across the "top" two pins of T301 followed by T302. I am also assuming you mean the blue little caps, not the big ones by the transformer that I replaced, correct? 306, 307, 309, 311 are their numbers.

[itsallbs]

Re: Samsung Syncmaster 225BW

Gentlemen I just wanted to report that I had a friend replace all the caps and I'm using it right now as I type! I took retiredcaps advice of using the panasonic FR's and also chose the united chemicon 565-1800's which happened to be in the cart by following the link. Kudos!

P.S. a little humor

I've been extremely clumsy since the repair was done. The LCD fell from my chair onto my foot and I also knocked over some hot chocolate all over my desk and keyboard while trying to set up the monitor as an extended monitor.

[retiredcaps]

Re: Samsung Syncmaster 225BW

1.098k and 1.097k if I understand your meaning.

Those measurements suggest the inverter transformer is okay since they are with 3% of each other.

That leaves the ccfl and/or its wiring to check next. See

http://s807.photobucket.com/albums/y...klight%20lamp/

for examples.

[michaelahess]

Re: Samsung Syncmaster 225BW

Yeah, ccfl's look burned out, very black and corroded on one end. Any idea where I can get them cheap? May be better to just get a new monitor at this point.

[retiredcaps]

Re: Samsung Syncmaster 225BW

Any idea where I can get them cheap? May be better to just get a new monitor at this point.

ccflwarehouse.com has good feedback from forum members here. They also have a tutorial at

http://www.ccflwarehouse.com/lasotu.html

that shows how to install new ones.

Replacing the new ccfls is very fragile work as one person just reported in this thread ...

https://www.badcaps.net/forum/showpo...7&postcount=38

[michaelahess]

Re: Samsung Syncmaster 225BW

Wow, after looking at that, I think it's time for a new monitor! Anyone want a newly fixed power supply? Only 7* months old!

Thanks for the help retiredcaps!

*ok, so the rest of the board maybe be about 5 years old

[Scenic]

Re: Samsung Syncmaster 225BW

look for cracked LCD screens on ebay or w/e.
either with model numbers of other monitors of the same size or with the model number of the panel itself.

that's the only way to get matching CCFLs really cheap.

i've got a 223BW (which is a 21.5" LCD, not a 22" one as the name suggest) with a fried logic board (won't turn on, all voltages are there and in spec..)

had to learn it the hard way that the 22xBW units seem to like to kill their logic boards..
of course, i found that out AFTER fixing the PSU up.. d'oh

[retiredcaps]

Re: Samsung Syncmaster 225BW

Wow, after looking at that, I think it's time for a new monitor!

If you follow the same thread, the OP took another shot at it using some of the original ccfls and has it working. See

https://www.badcaps.net/forum/showpo...4&postcount=42

[DrQuest]

Re: Samsung Syncmaster 225BW

Thanks for posting this site. I purchased what I needed for my 225BW as i use it as a side monitor for mail, etc. It's pretty old, but then saw this forum and the repair kit Hobby Mods sells and thought what the hell. I'll give my soldering iron of justice a try and see what happens.

Well... within an hour I had the caps replaced, put back together and hooked back to my PC and it works like a charm!

You may find capacitors for less money, but to get them all in one place in a nice little kit, with solder made it easy and worth the money. $6.99 + shipping beats a whole new monitor or paying someone else labor to do this.

https://www.hobbymods.com/store/inde...ent-parts.html

Thanks again for sharing this info on the web!

Cheers!

[andymona]

Re: Samsung Syncmaster 225BW

Hi, my monitor Samsung 225BW has been having problems turning on after sleep mode. Sometimes screen would be red tinted, sometimes would not turn on until after some button pushing or main power turning on and off couple times. Lately it would not turn on at all.
I've found out about the capacitors problem and replaced 2 of the following: CAP 820UF 25V ELECT LXY RAD, and 3 of this: CAP 330UF 25V ELECT FC RADIAL.
I did not touch the 47UF or the big 450V yet as they look really good.
It still does not work. Now when I turn it on the screen is black, power button blinks once and stays on blue even when I'm pushing it.
Please help.
Can you overheat the new cap during the installation to the point it wont work?

[alexanna]

Re: Samsung Syncmaster 225BW

Hi, my monitor Samsung 225BW has been having problems turning on after sleep mode. Sometimes screen would be red tinted, sometimes would not turn on until after some button pushing or main power turning on and off couple times. Lately it would not turn on at all.
I've found out about the capacitors problem and replaced 2 of the following: CAP 820UF 25V ELECT LXY RAD, and 3 of this: CAP 330UF 25V ELECT FC RADIAL.
I did not touch the 47UF or the big 450V yet as they look really good.
It still does not work. Now when I turn it on the screen is black, power button blinks once and stays on blue even when I'm pushing it.
Please help.
Can you overheat the new cap during the installation to the point it wont work?

I would inspect all the soldering you did on the capacitors you replaced, for any looseness.
Samsung gives me the most trouble, removing the old solder is difficult.

[andymona]

Re: Samsung Syncmaster 225BW

I would inspect all the soldering you did on the capacitors you replaced, for any looseness.
Samsung gives me the most trouble, removing the old solder is difficult.

Thank you for that. I've just both desoldering braid and 62/36/2 rosin-core solder and I'm going to repeat the process with new caps.
Do you think, though, it could be something different??? The power button (blue light) is always on after connecting power cord and I cannot turn the blue light off.

[jetadm123]

Re: Samsung Syncmaster 225BW

Hi, my monitor Samsung 225BW has been having problems turning on after sleep mode. Sometimes screen would be red tinted, sometimes would not turn on until after some button pushing or main power turning on and off couple times. Lately it would not turn on at all.
I've found out about the capacitors problem and replaced 2 of the following: CAP 820UF 25V ELECT LXY RAD, and 3 of this: CAP 330UF 25V ELECT FC RADIAL.
I did not touch the 47UF or the big 450V yet as they look really good.
It still does not work. Now when I turn it on the screen is black, power button blinks once and stays on blue even when I'm pushing it.
Please help.
Can you overheat the new cap during the installation to the point it wont work?

1) You probably don't need to replace the existing caps except for the 47uf cap, since it's required for starting the power supply. Also, check for bad solder joints like alexanna suggested.

2) The red tint you indicated might be a CCFL tube starting to fail.

3) With the monitor connected to a computer, hold a flashlight against the dark screen. Can you see a faint image?

[andymona]

Re: Samsung Syncmaster 225BW

1) You probably don't need to replace the existing caps except for the 47uf cap, since it's required for starting the power supply. Also, check for bad solder joints like alexanna suggested.

2) The red tint you indicated might be a CCFL tube starting to fail.

3) With the monitor connected to a computer, hold a flashlight against the dark screen. Can you see a faint image?

Thank you so much. I will order 47UF and then I will report with the results ASAP.
Do you think this is the one (47UF) I need?
http://search.digikey.com/scripts/Dk...name=P10267-ND

[jetadm123]

Re: Samsung Syncmaster 225BW

You did select the correct 47uf cap. However, since you are getting a power light, it would indicate that the power supply is starting up. You need to verify the output voltages of the supply before going any further. Also, please post some good focused photos of the top and bottom of the power board using the "manage attachments" button. Before buying the cap, you'll have to verify other components are good. Therefore, hold off on the purchase.

[andymona]

Re: Samsung Syncmaster 225BW

Hey!
You've said "You need to verify the output voltages of the supply before going any further". I need some hardware for that I'm sure. I hate radioshack, hopefully I can get that elsewhere...

Here are the requested pics:


What do you think? Are any other components toasted?