Samsung 245b Plus

[MuG]

Hi,

I would like some help reviving Samsung 245b Plus.
Model: 245BPLUS
Model Code: LS24HUBCBL/EDC
Type No: HU24BS

The Symptoms:
Monitor appears to be on(Blue Light on solid)
No signal to screen, no menu
Worked for a few days by turning it off for 30 seconds then on again but it eventually gave up


So far following your guide I have taken apart the monitor and removed the power board. Examined the board and documented the capacitors i see there. Please point out if I've missed any.
The Images
Sorry for the external link but my pics were too big and I dont have photo shop installed on my laptop to downsize the pics.

• Caps
  A: 10 uF 50v
  B: 47 uF 50v
  C: 1000 uF 35v *
  D: 1000 uF 35v *
  E: 1000 uF 10v
  F: 470 uF 35v
  G: 2200 uF 10v
  H: 2.2 uF 50v
  I: 47 uF 50v #
  J: 22 uF 50v
  K: 10 uF 50v
  L: 47 uF 50v #
  M: 82 uF 450v ?
  
  So it seems i need:
  1* 2.2 uF 50v
  2* 10 uF 50v
  1* 22 uF 50v
  3* 47 uF 50v
  1* 470 uF 35v
  1* 1000 uF 10v
  2* 1000 uF 35v
  1* 2200 uF 10v
  
  1* 82 uF 450v ??
  
  

To my untrained eye I don't see any sign of damage on the capacitors.

I have read this Samsung Syncmaster 245B thread
Should I bother changing the big 450v 82uF cap? I have not experienced flickering. If yes how would i go about discharging it?

I have compared the caps i need to the kit here and they do not match. Why do the kit contents not list voltage of the cap?

Thanks in advance for any help.

[retiredcaps]

Re: Samsung 245b Plus

Sorry for the external link but my pics were too big

The max resolution is 2000x2000 and I believe 2MB for jpgs.

To my untrained eye I don't see any sign of damage on the capacitors.

https://www.badcaps.net/forum/showpo...13&postcount=3

If yes how would i go about discharging it?

Most big caps in the LCDs monitors discharge via bleeder resistor in about 60 seconds or so. See the following if you want to learn more about discharging ...

http://www.repairfaq.org/sam/captest.htm#ctsdc

I have compared the caps i need to the kit here and they do not match. Why do the kit contents not list voltage of the cap?

Manufacturers can and have changed board revisions or put in completely different boards while keeping the same lcd model number.

[MuG]

Re: Samsung 245b Plus

Thanks for the quick response Retired.

My pics are 4k*4k

So my aim is to replace all caps marked on the pic except M(82 uF 450v). Safe to work on the other caps with this big one still charged once I am careful not to touch the solderpoints on the bottom of the board? The monitor has been off for about 2 weeks.

Mind having a look at my pics? The labelled ones, Have i missed any?

I understand that boards change with different revisions. Why are the voltage of the caps in the kits supplied not listed so we can better compare to what we have found?

Also I live in Ireland, So any help on what to order what I need from an irish or uk site like the ones listed in this thread would be much appreciated.

If you need any more pics, info please let me know. Thanks again.

[Scenic]

Re: Samsung 245b Plus

The Images
Sorry for the external link but my pics were too big and I dont have photo shop installed on my laptop to downsize the pics.

try something like this next time. simple and small
just make sure to uncheck the box to install google chrome with it...

[MuG]

Re: Samsung 245b Plus

Thanks for the link scenic. I had forgotten about irfanview

I have uploaded the resized pics, so should be less trouble to check them now. I do realise that I am missing a pic of the bottom of the board, sorry but this will have to wait till sunday when i'm home if needed.

Any word on if i have missed any caps from the marked diagram?
Any help on what to order from the UK/Irish sites linked above would be great.


EDIT: A way to remove the yellow gunk holding some groups of caps in place? Rubbing alcohol?

[smason]

Re: Samsung 245b Plus

For the gunk, you pretty much have to chip it/pry it off carefully.
I usually use a metal dental pick.

[Rtech]

Re: Samsung 245b Plus

Thanks for the quick response Retired.

Also I live in Ireland, So any help on what to order what I need from an irish or uk site like the ones listed in this thread would be much appreciated.

If you need any more pics, info please let me know. Thanks again.

The UK sites for your caps,have various problems for a one off purchase....RS and Farnell Minimum order of £20 PLUS VAT at 20%...Digikey, will want VAT as well,also £12.50 for P&P..the latter do not operate as per the US one I'm afraid.

[MuG]

Re: Samsung 245b Plus

Ok I see the situation. So what is the best way to proceed?
Do you think the good folks at badcaps.net would make me up a kit of the caps i need? It will take longer than i'd like this way but as an old irish saying goes "Sure what can you do"

[Rtech]

Re: Samsung 245b Plus

A quick Google ,suggested that,perhaps one of these Firms in Ireland, may be able to help ??.
http://electrical-electronic-equipme...omponents.html

Also I regularly replace 1000 uF 10V faulty caps,due to failure,and ALWAYS replace with 16v ones,provided they fit of course.

[jetadm123]

Re: Samsung 245b Plus

Ok I see the situation. So what is the best way to proceed?
Do you think the good folks at badcaps.net would make me up a kit of the caps i need? It will take longer than i'd like this way but as an old irish saying goes "Sure what can you do"

There's also a seller on eBay that sells a repair kit. However, their parts list is a little different than yours. Probably wouldn't hurt to ask if they can substitute caps to match your list.

[MuG]

Re: Samsung 245b Plus

I have found a solution, 1 of your members from the UK pm'ed me and is going to ship me the caps i need.
Thanks for all the input guys. Will let you know how i get on with the fix.

[MuG]

Re: Samsung 245b Plus

Hi guys. I received the caps yesterday and went through the recapping process.

Unfortunately, I am a complete amateur at soldering and I have damaged the PCB. Please forgive my horrible blobby soldering, I improved near the end of the job :P

Shown in the pics below

10052011088.jpg shows a solder pad with "minor" damage

10052011089+.JPG Quick paint edit
The blue line is the solder pad that I found after removing it while desoldering.
The red line is the exposed PCB area

Options?

[retiredcaps]

Re: Samsung 245b Plus

The red line is the exposed PCB area

The best soldering video is by CuriousInventor at

http://www.youtube.com/watch?v=I_NU2ruzyc4

For the solder joint circled in red, you will have to use a multimeter to see if there is continuity between that capacitor leg/pad and the right hand leg of the chip that is marked WC.

If there is continuity, you can run a jumper wire between the two.

[tgu]

Re: Samsung 245b Plus

Friday 13th.. Luckily it wasn't any worse that this.

I have similar problem with Samsung SyncMaster 245B Plus too. Yesterday it started blinking black (0.5 sec about every 20 minutes) and today it gave up completely. Black screen with blue power on and with no menus. Tried to switch cables but no result. Soon I found this site and few 245B topics.

some specs:
Model: 245BPLUS
Model Code: LS24HUBCBL/EDC
Type: HU24BS
Power board (my bad english): BN44-00195A

Country: Finland (230V)

I'll get some pictures in few days, but all the capacitors seem to be fine (with my untrained eye). I hope to get some guidance and tips here, but I also try to read up all the other similar topics trough. At the moment I'm learning to be an electrician, so at the moment I have basic understanding about these components. And as for the soldering, seems like those capacitors and resistors are easy to change.

[jetadm123]

Re: Samsung 245b Plus

Friday 13th.. Luckily it wasn't any worse that this.

I have similar problem with Samsung SyncMaster 245B Plus too. Yesterday it started blinking black (0.5 sec about every 20 minutes) and today it gave up completely. Black screen with blue power on and with no menus. Tried to switch cables but no result. Soon I found this site and few 245B topics.

some specs:
Model: 245BPLUS
Model Code: LS24HUBCBL/EDC
Type: HU24BS
Power board (my bad english): BN44-00195A

Country: Finland (230V)

I'll get some pictures in few days, but all the capacitors seem to be fine (with my untrained eye). I hope to get some guidance and tips here, but I also try to read up all the other similar topics trough. At the moment I'm learning to be an electrician, so at the moment I have basic understanding about these components. And as for the soldering, seems like those capacitors and resistors are easy to change.

Since you're getting a power light, it sounds like the logic board is getting 5V. The black screen indicates the backlight is not coming on. Do you get a flash of light at all when you first turn on the monitor? Or is the screen always completely black?

Depending on how you answer, it could be bad caps, a blown fuse feeding the inverter, bad transformer on the inverter, bad ccfl, bad ccfl wiring, or a problem with the sense circuit that shuts down the inverter. Also, the power supply may not be outputting the correct voltage to the inverter.

Hope that you now understand why we ask for photos. When you do supply the photos, please post them using the "manage attachments" button and also include a photo of the inverter and logic boards.

[tgu]

Re: Samsung 245b Plus

After it went all black during use, it has been completely black afterwards. Switching power led on/off and power switch under panel doesn't bring any light on the screen. Here's some pictures of the components.

Edit: Both fuses are fine. I'll be back tomorrow to continue.

[Toasty]

Re: Samsung 245b Plus

With the PSU back in the frame and connected - except for the plug from the PSU to the Inverter.
Try powering on and see if you have 24v on the pins of the PSU as indicated by the table on the Inverter board.
5 @ 24v(+) and 5 @ Ground(-).

Check the 4 inverter MOSFETs for shorts. Check the inverter fuse for continuity.

Some clear pictures of the underside of the PSU too, please.

Toast

[tgu]

Re: Samsung 245b Plus

Got my tools back to home, and bought some rubber gloves just in case :P
Here's some pictures from underside.

I'll update results later tonight.

[tgu]

Re: Samsung 245b Plus

On PSU 5x24V and 5xgnd give 24.4V each, they seem to work. Inverter fuse on board gives a continuity beep. Searching instructions for testing them MOSFETs.

[Toasty]

Re: Samsung 245b Plus

Diode check with DMM or low ohms scale with analog. Check for shorts between legs and tab in all polarities.

Hook the PSU to inverter cable back up and monitor the 24v on the inverter board as you cycle the power button. If 24v jumps up briefly then dies, the problem is in the inverter.