Dell 2407WFPb Monitor - Bad Cap

[Pentium4]

Re: Dell 2407WFPb Monitor - Bad Cap

I too thought that primary caps never failed until I opened up a 24 port gigabit switch to find a slightly bulging 100uf 400V Taicon cap

[retiredcaps]

Re: Dell 2407WFPb Monitor - Bad Cap

I too thought that primary caps never failed until I opened up a 24 port gigabit switch to find a slightly bulging 100uf 400V Taicon cap

Big caps, rarely, but not never fail. Sometimes the big cap looks bulged, but is not. If you press down on the big cap, is it flat?

[DrNegative]

Re: Dell 2407WFPb Monitor - Bad Cap

Ok, you should all really stop discussing solutions! The solution to repair the powerboard has passed this topic a few times now:

Buy these parts (farnell number = first number):
1469418 VISHAY SEMICONDUCTOR TZMC15-GS08 DIODE, ZENER, 15V, 0.5W
1828683 PANASONIC CAPACITOR, SNAP-IN, 450V, 120UF
2*1903859 MULTICOMP RESISTOR, WIREWOUND, 0R47, 5%,
1652430 SEMICONDUCTOR NCP1200D100R2G
9882464 STMICROELECTRONICS
9935517 STMICROELECTRONICS STP10NK60ZFP MOSFET, N, TO-220FP
1354592 LITTELFUSE 0234004.MXP FUSE, MEDIUM DELAY, 4A
1162740 SCHURTER 0031.8201 FUSE HOLDER, PCB,
9693904 ECA2AM010 CAPACITOR, 1UF, 100V (optional to replace)
& 1k resistor in 0805 size or 1206


And replace:
-C605 120uF/450V
-Q651 STP10NK60ZFP
-IC651 L6561D
-R669 1k 1206
-ZD601 15V 0.5W (diode)
-IC601 NCP1200D
-R670 = 2*0.47ohm together parallel (makes 0.23ohm)

This will definitely solve most of the problems! Pictures with the pieces that should be replaced are attached. These are images of a repaired working board.

Fixed 2 Dell 2407WFPb screens with the replacement of these parts.

I just signed up for the forums to say thank you for this post. Using your hi-res pictures and parts list, I ordered my replacement parts from Digi-key and successfully repaired my Dell 2407 tonight and I am typing on it right now.

You saved me a lot of money. Well done.

[bootlegger17]

Re: Dell 2407WFPb Monitor - Bad Cap

I just want to say a big thankyou to everyone in this forum for their dedication and support. With your help and the parts list assembled by micdis, I was able to buy all parts from Farnell for £15 inc postage, and got a 2407WFPb monitor working!

From my experience, I had a few little troubles.
1) the 1828683 PANASONIC CAPACITOR, SNAP-IN, 450V, 120UF part sent by Farnell was a short stubby model, not quite the same as the original removed part. It did not have any legs and so I had to improvise some legs from some resistors that I had.
Would any one know if the resistor legs from the wirewound resistor mentioned in the parts list by micdis is enough gauge to carry the voltage required by the 450v 120uf cap? It seems to work so far, but am a little concerned about running the monitor for a long time because of this.
2) On removing the NCP1200, I managed to lift some tracks (pins 7,and 6!). Having downloaded the schematics for this part, I worked out that pin 7 was not connected anyway. Pin 6 was the Vcc, so I traced the track underneath the part that led to a resistor to the side of the part, and it also connected to a cap on the other side of the board.
3) I could not read my label on the 6561 component. Looking at the pictures on this forum, I couldnt make out which way the chip was supposed to be fitted. Again, schematics helped me out again to work out correct orientation for this part.
I also examined all other components and they all seemed to be orientated the same way, so this gave me a lot of confidence that I had it the right way around.

So once again, many thanks to everyone for their support.
Regards
Jason

[jetadm123]

Re: Dell 2407WFPb Monitor - Bad Cap

Bootlegger17-Congrats on a successful repair. It's refreshing to see someone actually look at the data sheets and use them to aid in the repair of their monitor.

The resistor wire you used should at least be the same thickness as the 1 Watt resistors that are on the board now. Or better yet, compare the thickness to the wire of the original cap you replaced.

[bootlegger17]

Re: Dell 2407WFPb Monitor - Bad Cap

Hi JetAdm
The size is just slightly smaller, but also, the legs are a lot more flexible and bendable than the original also cap. I will keep an eye out for 'something' better quality and replace it in due course, but at the moment it seems to be holding up ok

[sebr]

Re: Dell 2407WFPb Monitor - Bad Cap

Ok, you should all really stop discussing solutions! The solution to repair the powerboard has passed this topic a few times now:

Buy these parts (farnell number = first number):
1469418 VISHAY SEMICONDUCTOR TZMC15-GS08 DIODE, ZENER, 15V, 0.5W
1828683 PANASONIC CAPACITOR, SNAP-IN, 450V, 120UF
2*1903859 MULTICOMP RESISTOR, WIREWOUND, 0R47, 5%,
1652430 SEMICONDUCTOR NCP1200D100R2G
9882464 STMICROELECTRONICS
9935517 STMICROELECTRONICS STP10NK60ZFP MOSFET, N, TO-220FP
1354592 LITTELFUSE 0234004.MXP FUSE, MEDIUM DELAY, 4A
1162740 SCHURTER 0031.8201 FUSE HOLDER, PCB,
9693904 ECA2AM010 CAPACITOR, 1UF, 100V (optional to replace)
& 1k resistor in 0805 size or 1206


And replace:
-C605 120uF/450V
-Q651 STP10NK60ZFP
-IC651 L6561D
-R669 1k 1206
-ZD601 15V 0.5W (diode)
-IC601 NCP1200D
-R670 = 2*0.47ohm together parallel (makes 0.23ohm)

Thanks for the list, on my PCB all the mentioned parts are blown plus these:

R674
Q654

Earlier in this thread it was mentioned that R674 could probably be read as "8251". Would be nice if anybody can confirm this to 100% before I place my order

[elvena]

Re: Dell 2407WFPb Monitor - Bad Cap

Yep, most of them are usually blown, mine had some other parts blown too (post #254) like Q654 and the diode you mention was ok (ZD601 15V 0.5W)

Basically everyone should check ALL the different parts mentioned on this thread.

Oh BTW, I'm using a 120uF/400V Nichicon capacitor, didn't find anywhere a 120uF/450v.

Almost two months !

Ok, you should all really stop discussing solutions! The solution to repair the powerboard has passed this topic a few times now:

Buy these parts (farnell number = first number):
1469418 VISHAY SEMICONDUCTOR TZMC15-GS08 DIODE, ZENER, 15V, 0.5W
1828683 PANASONIC CAPACITOR, SNAP-IN, 450V, 120UF
2*1903859 MULTICOMP RESISTOR, WIREWOUND, 0R47, 5%,
1652430 SEMICONDUCTOR NCP1200D100R2G
9882464 STMICROELECTRONICS
9935517 STMICROELECTRONICS STP10NK60ZFP MOSFET, N, TO-220FP
1354592 LITTELFUSE 0234004.MXP FUSE, MEDIUM DELAY, 4A
1162740 SCHURTER 0031.8201 FUSE HOLDER, PCB,
9693904 ECA2AM010 CAPACITOR, 1UF, 100V (optional to replace)
& 1k resistor in 0805 size or 1206


And replace:
-C605 120uF/450V
-Q651 STP10NK60ZFP
-IC651 L6561D
-R669 1k 1206
-ZD601 15V 0.5W (diode)
-IC601 NCP1200D
-R670 = 2*0.47ohm together parallel (makes 0.23ohm)

This will definitely solve most of the problems! Pictures with the pieces that should be replaced are attached. These are images of a repaired working board.

Fixed 2 Dell 2407WFPb screens with the replacement of these parts.

[sebr]

Re: Dell 2407WFPb Monitor - Bad Cap

Another SUCCESS here!
I replaced all the parts listed two posts above and the unit is working.
Beside that I highly recommend to change the five output caps and the three caps on the inverter, like some people here already suggested. They are also Elite brand.

PS: R674 is marked "8251", now I can confirm.

[leapius]

Re: Dell 2407WFPb Monitor - Bad Cap

I have an inverter problem as detailed here:

https://www.badcaps.net/forum/showthread.php?t=22549

I was wondering are these five output caps you refer to the tiny SMD ones on the intverter? If so which are you talking about exactly. Also do you know what I need to buy to replace them. I have already changed the three big ones on the inverter to no avail.

Thanks

[budm]

Re: Dell 2407WFPb Monitor - Bad Cap

@leapius, did you do any resistance reading on the inverter transformer yet? Do you have about 19vdc at the inverter fuse?
https://www.badcaps.net/forum/showth...fpb#post245054

[sebr]

Re: Dell 2407WFPb Monitor - Bad Cap

I'm talking about C711-C715 on the PSU board. I replaced them with Panasonic FC/FM caps just as I did with those three from the inverter. If after that your CCFL don't come up fully, I would suggest looking for cold soldering joints (inverter).

[leapius]

Re: Dell 2407WFPb Monitor - Bad Cap

@leapius, did you do any resistance reading on the inverter transformer yet? Do you have about 19vdc at the inverter fuse?
https://www.badcaps.net/forum/showth...fpb#post245054

I checked the standby voltage from F1 to GND and it is a solid 19v as per this photo: https://www.badcaps.net/forum/attach...2&d=1339721233

I (think) I checked the resistance of the secondary windings of each inverter and they are all around the 960-990ohm range. I was told by someone else that the problem could lie in the small surface mounted capacitors but I am lost to know which it could be or what I would replace them with. There are loads of those.

[zenerdiode]

Re: Dell 2407WFPb Monitor - Bad Cap

Another SUCCESS here!
I replaced all the parts listed two posts above and the unit is working.
Beside that I highly recommend to change the five output caps and the three caps on the inverter, like some people here already suggested. They are also Elite brand.

PS: R674 is marked "8251", now I can confirm.

I have a monitor with ic 651 blown actually cracked. Also R 674 is blackened and in addition R 678 is beyond readint the value. Do you know it's value? thanks zener diode

[selldoor]

Re: Dell 2407WFPb Monitor - Bad Cap

I have a monitor with ic 651 blown actually cracked. Also R 674 is blackened and in addition R 678 is beyond readint the value. Do you know it's value? thanks zener diode

Id say few of us have this set open most will never see one.
Try cleaning the components with isopropyl alcohol. Have you searched through the threads / online for pictures that might show them.

[sebr]

Re: Dell 2407WFPb Monitor - Bad Cap

Here you go: https://www.badcaps.net/forum/attach...4&d=1316486210

[budm]

Re: Dell 2407WFPb Monitor - Bad Cap

Here:
R674 = 8251 = 8250 Ohms (I measured it to verify)
R678 = 103 = 10K Ohms

More pictures here:
http://s807.photobucket.com/albums/y...ll%202407WFPB/

More power supply board:
http://s807.photobucket.com/albums/y...upply%20board/

[FrenchKheldar]

Re: Dell 2407WFPb Monitor - Bad Cap

Hi,

Complete newbie here. I just moved from Atlanta, GA to Albany, NY and when I unpacked my 2407 WFPb, plugged it in and tried to power it on, the power button lit up and then went blank immediately. No sound, no smoke that I noticed. After a fair bit of traveling in December, I'm ready to come back home and take care of this. I have skimmed through this thread and spent a little time researching the net for this problem, and while some people have some success, it seems like it is far from a trivial fix. I would like your opinion on my options:
- try to fix this myself. I might have a soldiering iron lying around somewhere but I don't have much else and I have very little experience fixing electronics. And my previous experience with manual electronic labor has been poor (not really the crafty kind): for example, when I opened my MacBookPro to replace the optical drive with a SSD, I was successful but managed to hose one of my speaker cable.
- bring my monitor to a professional and have it fixed for less than a price of a shitty replacement monitor (say $100-$150). I am new to my area so I'm not sure what kind of service I can get easily... Looking at the price of 1920x1200 monitors, I think it might still be a decent deal for me. In an ideal world, I was planning on upgrading that monitor at the end of 2013 but currently funds are too low for the equivalent top of the line Dell (2711 I believe)
- in the event I decide to buy a new monitor, what should I do with the current one? Seems like a waste to recycle it if most of the components are good. How would I go to find it a new home?

Hopefully my questions are somewhat in line with the forum, thanks in advance for your help.

[selldoor]

Re: Dell 2407WFPb Monitor - Bad Cap

I would say have a look -do a few tests if it is too much then you can rethink what to do.
You will need a multimeter to do basic tests - a 5$ one will do.
If you are really lucky getting the back off may be the hardest part. Oh and taking good photos of it

Welcome to the forum-
We can help a lot more if you please post good clear pictures of the whole chassis, and then pictures of each board, front and back (in the same orientation) and close up of connectors, (max resolution 2000x2000 and 2MB) using the manage attachments button, which is found by clicking "go advanced" under quick reply.

Please do not post inline and offsite as they slow down the loading of pages.

Examples of what is needed

https://www.badcaps.net/forum/attach...7&d=1280167246

https://www.badcaps.net/forum/attach...6&d=1280167246

https://www.badcaps.net/forum/attach...4&d=1280167246

[FrenchKheldar]

Re: Dell 2407WFPb Monitor - Bad Cap

Thanks a lot for the pointers, I will get these pictures as soon as I'm back in Albany.