Smasung SyncMaster 913N Monitor wouldnot display images

[PlainBill]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Thanks for your reply Daniel...I have replaced all of the caps on the board except for the "big boy" and only get the dim picture. I performed the voltage check on the board as described earlier in this post and the voltages are normal: The big cap is running 165v (us) and the smaller ones are steady at 13v. I also checked the fuse on the board, and it is good. I didn't check output voltage to the ccfl's, is there a certain way I should do this, anyone?

Don't check the voltage to the CCFLs unless you have a DMM capable of handling 1000 Volts at 100 Khz.

This is a strange problem. If the monitor is acting normally EXCEPT the display is very dim (but the CCFLs are producing light, it isn't necessary to use a bright light), try adjusting the brightness (it might be easier in a dark room).

If you can only see anything on the monitor if you use a light source external to the monitor there is a problem with the inverter.

PlainBill

[samainfirenight]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Thanks for your reply Daniel...I have replaced all of the caps on the board except for the "big boy" and only get the dim picture. I performed the voltage check on the board as described earlier in this post and the voltages are normal: The big cap is running 165v (us) and the smaller ones are steady at 13v. I also checked the fuse on the board, and it is good. I didn't check output voltage to the ccfl's, is there a certain way I should do this, anyone?

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

samainfirenight,

I'm not the most knowledgable about fixing monitors/electronics however you can try replacing the big cap. On my monitor the front led was flashing really fast and would get brighter and less brighter which I thought was a power supply issue ie not enough power being dished out. Our mains voltage is 230vac in the uk and when i measured the big cap it was 160v, however when I replaced the big cap the voltage was sitting at a stable 312v and the screen was working. Your big cap could be on its last legs and thats why you can only see a dim picture. Saying that though are the backlights working on the monitor?

I'm sure others will reply on here and guide you in the right direction. I did replace all of the caps PlainBill asked me to which in total was 12. My monitor is still working great.

Daniel

[samainfirenight]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

I have a syncmaster 203B, will this testing method work on it? I have been troubleshooting and trying to repair this monitor with no luck. I have replaced all caps except for "big boy" but still can't get it to work. I don't have any board to interchange with either.

All I can get it to do is the Dimly lit picture. When I got my hands on the monitor, it would not power on at all, just blinking led. After replacing the blown caps, and the ones that showed no visible damage, the monitor will "power up" but the picture is BARELY visible.

I really want to get this monitor to work

[EGuevarae]

Re: Smasung SyncMaster 913N Monitor wouldnot display images





Now that's a BIG BOY ....

Another one saved from the landfill ..... good job.

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

Yeah I'd definitely check the "Big Boy" first.

Daniel

[PlainBill]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Hi Guys,

Good news I replaced the 100uF 450v cap and the monitor came back to life. The cap wasn't exactly the same size but it works. I had to make a holes in the metal chassis but that's down to me not measuring all the replacement caps before buying. I've taken a few pictures for you guys to see the handy work which isn't amazing in this attempt. The next monitor I fix will be done much much better than this but you can't beat experience I suppose. The monitor is running great/normal but I will have to test to however for now its good. I did replace 12 caps in total so I shouldn't have any future issues.

I'm definently going to re-think any future monitor/tv purchases and recommendations because its kinda annoying samsung are using this crappy components ie crapxon.

I'd like to thank all of you guys especially PlainBill your help has been great, I plan to stick around and help others out. I am sure there will be someone else who has had the same problem and needs a fix which is proven and works, well certainly in my case.

Thanks guys.

Daniel

I'm glad to see it's working. Perhaps the first step of my instructions should be 'Check the voltage at the main filter capacitor.'

PlainBill

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Hi Guys,

Good news I replaced the 100uF 450v cap and the monitor came back to life. The cap wasn't exactly the same size but it works. I had to make a holes in the metal chassis but that's down to me not measuring all the replacement caps before buying. I've taken a few pictures for you guys to see the handy work which isn't amazing in this attempt. The next monitor I fix will be done much much better than this but you can't beat experience I suppose. The monitor is running great/normal but I will have to test to however for now its good. I did replace 12 caps in total so I shouldn't have any future issues.

I'm definently going to re-think any future monitor/tv purchases and recommendations because its kinda annoying samsung are using this crappy components ie crapxon.

I'd like to thank all of you guys especially PlainBill your help has been great, I plan to stick around and help others out. I am sure there will be someone else who has had the same problem and needs a fix which is proven and works, well certainly in my case.

Thanks guys.

Daniel

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Hi,

On the video board it has two chips one has samsung magic colour written on it and the other has a white label on it which reads

MJ19E_9.IE
2005.10.11
47EF

That top code may or may not be any use anyone. I appreciate your comments regarding the out of range however in my case the monitors power led (green) flickers very rapidly. On reflection of this and what's been discussed on here I do believe that is caused by a power problem (power fluctuationing or not enough power). The replacement large cap or "Big Boy" as its been named should be here today if royal mail get a move on, people in the UK will know what I'm talking about.

Daniel

[gonzo0815]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Those NT68F63L are already programed, but you can program it by your own with the EasyWriter software from Novateck and a simple LPT > VGA adapter.
So you should be able to save your original firmware (careful, obey the correct checksum) and program it to the new chip.
ATM i do not know which chip is the right one, if no of them offered match your four digit code. But for the 913N i think they do offer one. or simply ask the seller.
I have replaced the video board completely in my 913N and it wasn`t the original one. The monitor does now have another DDC name, but that doesn`t hurt.

Removing the PLCC chip could be done by cutting the pins with a dremel or a precise cutting tool, then desoldering the pins one by one. This should be easy if done carefully.
Hot air gun is another possibility, but some care have to be taken to avoid desoldering some SMD devices, as the whole pcb would become hot.

As some hesitate to believe it, if your Syncmaster has the "out of range" problem or it does nothing when connected to a VGA card, no capacitor or psu swap will fix it.
And probably no other hack will do it in the long run. You have to replace the video chip, in this case the NT68F63L.

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

Guys,

It would be an old psu I have lying around screwed onto the back by the mounting screws and just being used to power the monitor. I'd have to get the correct voltage though for whats required. I'll have a play.

This is where I got the idea:

http://computerguru365.blogspot.com/...l-monitor.html

Personally I'd rather fix what I have because it looks better and it would be good because I've got three other types of this monitor which could have the same issue. The psu on the back is the last resort however if it works it'll save a 19inch from being scrapped.

Dan

[EGuevarae]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

I'm not a fan of that approach. Certainly it is possible (in some cases). A lot depends on what you plan on doing with the monitor. An obvious consequence is the monitor and pc are tied together.

PlainBill

I've done it, but you need to be sure your PSU could handle both your PC and the LCD. I did it just as an experiment, and I am not using a monitor that way currently. I used it like that for like a month.

[PlainBill]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

I see. I've got a replacement big cap coming so I'll replace it and see if that works. Knowing my luck it probably is the big one and simply replacing it will fix it. However I cannot see any bulging on the cap or anywhere else I have replaced caps.

Either way if it works or not this has been a great learning experience. I have seen forum post somewhere else about some guy using a pc psu in order to power his monitor although I'd need to look into this. There are also four connectors on this board two at the top and at the bottom which I believe are for the backlight and they would need powering.

Daniel

I'm not a fan of that approach. Certainly it is possible (in some cases). A lot depends on what you plan on doing with the monitor. An obvious consequence is the monitor and pc are tied together.

PlainBill

[EGuevarae]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

I guess it makes sense. There is some debate on replacing the big cap. I usually don't bother. One guy said he had repaired over a hundred monitors and had only one where the big cap had failed. Between those I've fixed personally and those I gave advice to here, the total comes close to 100. Too bad yours was the one.

PlainBill

Around 80, Never had to replace the big boy.
Eduardo

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

I see. I've got a replacement big cap coming so I'll replace it and see if that works. Knowing my luck it probably is the big one and simply replacing it will fix it. However I cannot see any bulging on the cap or anywhere else I have replaced caps.

Either way if it works or not this has been a great learning experience. I have seen forum post somewhere else about some guy using a pc psu in order to power his monitor although I'd need to look into this. There are also four connectors on this board two at the top and at the bottom which I believe are for the backlight and they would need powering.

Daniel

[PlainBill]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

I have finished testing the working monitors PSU. Th results are below.


1= pin 1 - red // 9= pin 9 black

1 = 12.99 stable
2 = 12.99 stable
3 = 0.01
4 = 0.01
5 = 0.01
6 = 5.02 stable
7 = 5.02 stable
8 = 0.01
9 = 4.19 stable

large cap

test 1 = 312 stable
test 2 = 312 stable
test 3 = 312 stable

Those numbers are what I would expect. At a guess, 1 and 2 are for the bucking supplies on the video (logic) board. 3,4,5 are ground. 6 and 7 are the 5V supply to the video (logic) board. 8 is the backlight control, and 9 is brightness.

Try as I might, I can't come up with any logical explanation (other than a bad cap) for the other voltage being low. I doubt that a bad bridge would do it; a bad thermistor would be glowing red from the power it was dissipating.

I guess it makes sense. There is some debate on replacing the big cap. I usually don't bother. One guy said he had repaired over a hundred monitors and had only one where the big cap had failed. Between those I've fixed personally and those I gave advice to here, the total comes close to 100. Too bad yours was the one.

PlainBill

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

I have finished testing the working monitors PSU. Th results are below.


1= pin 1 - red // 9= pin 9 black

1 = 12.99 stable
2 = 12.99 stable
3 = 0.01
4 = 0.01
5 = 0.01
6 = 5.02 stable
7 = 5.02 stable
8 = 0.01
9 = 4.19 stable

large cap

test 1 = 312 stable
test 2 = 312 stable
test 3 = 312 stable

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

I will do the same checks on a working monitor. I replaced all the caps the correct way. I have a replacement cap coming for that 100uF 450v.

Daniel

[PlainBill]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

Thanks for your time. I have done what has been asked and the results are below:

red is pin 1 and working from the red pin right to pin 9 left.

1 = 10 to 12 volts
2 = 10 to 12 volts
3 = 0
4 = 0
5 = 0
6 = 0.80 to 1.70
7 = 0.80 to 1.90
8 = 0.96 to 1.70
9 = 0.09 to 1.60

large cap 216v stable - I tested it three times and it came back with 216v, Our mains voltage is 230vac.

Daniel

Well done. Unfortunately, I'm confused. The voltage across the large cap should be about 320 volts. If the cap were bad I would expect to see some fluctuation there. The voltages on pins 6-9 could indicate there is an excessive load on the 5 volt supply.

I hate to ask this, but would you please do the same measurements on a working monitor.

EDIT: I'm rethinking this. Replace the large cap. It can't be an excessive load on the Power supply / inverter board; one from a good monitor works fine. The voltage on the large cap is VERY low. There are only a few explanations for that, the cap, the thermistor, and possibly the bridge rectifier.

Reedit: Double check the orientation of all the caps you replaced. I've been burned by that mistake myself.

PlainBill

[dan86]

Re: Smasung SyncMaster 913N Monitor wouldnot display images

PlainBill,

Thanks for your time. I have done what has been asked and the results are below:

red is pin 1 and working from the red pin right to pin 9 left.

1 = 10 to 12 volts
2 = 10 to 12 volts
3 = 0
4 = 0
5 = 0
6 = 0.80 to 1.70
7 = 0.80 to 1.90
8 = 0.96 to 1.70
9 = 0.09 to 1.60

large cap 216v stable - I tested it three times and it came back with 216v, Our mains voltage is 230vac.

Daniel