Dell 2407WFPb Monitor - Bad Cap

[sgt_az]

Re: Dell 2407WFPb Monitor - Bad Cap

I've got a Dell 24" monitor that has burnt surface mount components. One is a transistor (Q654). The part has the following markings: "ZA 49". I can't find any information on that part number. Does anyone know where I can find a cross for it? The second burnt component is IC651. I can't read anything on IC651 but I found the part number through another BadCaps thread. https://www.badcaps.net/forum/showthread.php?p=178133 The 120uf 400V capacitor is also bad. Any information on Q654 would be greatly appreciated. Thanks.

[pkanar]

Re: Dell 2407WFPb Monitor - Bad Cap

Q654: 2N3906S by KEC (PNP transistor 40V, 350mW, in SOT-23 package)
IC651: L6561 by ST Micro (power factor corrector, in SO8 package, can also use L6562)
C605 is 450V

[BastiaanNaber]

Re: Dell 2407WFPb Monitor - Bad Cap

Can anyone tell me how IC651 is supposed to be oriented on the board? Attached is the picture of my replacement part and also the way that I'm holding the board. Thanks in advance!

[sgt_az]

Re: Dell 2407WFPb Monitor - Bad Cap

IC651 should be oriented with pin 1 down and to the left by the black dot on the board. Pin 1, where the indention is on the encapsulant, should be toward capacitor C621 just below it in the orientation you took the photo in.

[BastiaanNaber]

Re: Dell 2407WFPb Monitor - Bad Cap

Thanks everyone for your help. I have been able to restore my wives monitor.

I have replaced the following:

R670 0.22ohm Farnell 1903854 (10)
C605 120uF/450V Farnell 1828683
IC651 L6561D Farnell 9882464
IC601 NCP1200D Farnell 1652430
Q651 STP10NK60ZFP Farnell 9935517
ZD601 15V 0.5W (diode) Farnell 1469418
Fuse holder and Fuse Farnell 1162740 and 1354592

I hope it will keep going for a while. I will also replace the big cap in my own 2407, just in case.

[jetadm123]

Re: Dell 2407WFPb Monitor - Bad Cap

Glad to finally see some success stories for this monitor. And thanks for sharing your success story with us. Just out of curiosity, was the large 120uf leaking?

[pkanar]

Re: Dell 2407WFPb Monitor - Bad Cap

All failures of the big cap seem to be the same: no evidence of leaking, but corrosion and eventual disconnection where + terminal enters the body.

[oko]

Re: Dell 2407WFPb Monitor - Bad Cap

Hi guys, help determine which there were? received in this form! thanks for the help! may have a schematic for this power supply??

[VIPER1988a]

Re: Dell 2407WFPb Monitor - Bad Cap

i tried the external power mod that is on page 8 or 9 of this thread. still no go. i get 20v on yellow orange and red wires to inverter board, 20v on red wire to display board, and only 1v on the green wire to display board. i believe the green wire is supposed to be 7v. any ideas where the issue could be? the external supply i used was 90w 20v 3.5a

[budm]

Re: Dell 2407WFPb Monitor - Bad Cap

The main power supply is only single output around 19VDC, then other switching power supplies on another board are generated from this 19Vdc for running other circuits.
http://s807.photobucket.com/user/bud...?sort=3&page=1

[VIPER1988a]

Re: Dell 2407WFPb Monitor - Bad Cap

forgot to mention. i have the 2405fpw not the 2407

[budm]

Re: Dell 2407WFPb Monitor - Bad Cap

Oh, OK. What DC voltage do you get at the main 450VDC filter cap, measure right at the two pins of the cap? Can you also post the pictures of your board and the location of the pins you are measuring the voltage?
"i tried the external power mod that is on page 8 or 9 of this thread. still no go. i get 20v on yellow orange and red wires to inverter board, 20v on red wire to display board, and only 1v on the green wire to display board. i believe the green wire is supposed to be 7v. any ideas where the issue could be? the external supply i used was 90w 20v 3.5a" since the pin out of the 2407 are not the same as 2407, we need verification, especially 20v for the DISPLAY (T-CON?) is not right at all, it should be ONLY either 5 or 12V or may be you mean the MAIN Board?.
The Green and Blue wire on the whit connector of the power supply that goes to the main board are for BL_ON (Backlights ON), and Backlights Dimming signals which are generated by the main board and routed through the power supply board out at the other connector of the power supply board to the Inverter board.

[lexwalker]

Re: Dell 2407WFPb Monitor - Bad Cap

Hi guys, help determine which there were? received in this form! thanks for the help! may have a schematic for this power supply??

Just trace the pins and figure out the circuit. From the picture, judging from the SMPS transformer nearby, I would guess those missing ones are schottky rectifiers. If the connections to the pins are direct from the transformer then definitely they are rectifiers.

[oko]

Re: Dell 2407WFPb Monitor - Bad Cap

I can not afford so check out! to the name of the element choby I could buy and put them in there, help me please:!

[pkanar]

Re: Dell 2407WFPb Monitor - Bad Cap

I can not afford so check out! to the name of the element choby I could buy and put them in there, help me please:!

I don't have a 2405, or have the 2407 board handy, but looking at the picture (page 5 of this thread), they look like Schottky rectifiers/diodes in TO220FP package (common cathode on middle pin). The 5 capacitors are 470μF, 35V, 105°C (Elite EJ series).

[Nickkip]

Re: Dell 2407WFPb Monitor - Bad Cap

Hi Guys I have a problem with the same power supply 48.L1E02.A03 its reading short on a few places im still new to this. Would be great if anyone could point me in the right direction

R615 is short

C 611 is short

ZD601 is short

[budm]

Re: Dell 2407WFPb Monitor - Bad Cap

Please post good clear pictures of YOUR board. R615 is 0.22 Ohm resistor, so what do you read on your meter. Pictures of C611, ZD601?

[Nickkip]

Re: Dell 2407WFPb Monitor - Bad Cap

Hi Thanks for your replay I will post a video up to youtube bit later on see if I can show what im getting as where the top of the board by r615 that part of the board is all going to grown.

[Nickkip]

Re: Dell 2407WFPb Monitor - Bad Cap

Have uploaded the video to Youtube had no one to hold the camera for me will upload a better one tomorrow but think you may be able to get the idea. all the top right is short

http://youtu.be/ICJcvwSdgIQ

[Nickkip]

Re: Dell 2407WFPb Monitor - Bad Cap

here is a photo on other side