Dell 3008wfp faulty power supply

[heikkit]

Re: Dell 3008wfp faulty power supply

I have a Dell 3008 WFP that does power on normally but the image is partially messed up as shown in the attached picture. I suppose this is not power supply related but if someone has any ideas what to fix I'd appreciate it very much.

I haven't opened up the display yet so I don't know if there's any visible indications of broken components. I have waited for the display to heat up but that doesn't make any difference. The colour of the lower part of the display responds to input signal but with a delay of several seconds. The problematic area is visible even when there's no input signal.

[wuudi]

Re: Dell 3008wfp faulty power supply

Does anybody in europe (germany,italy) have some STPS40170CT left from multipack? I can only find them at RS components and have to buy a pack of 5...

[fuus]

Re: Dell 3008wfp faulty power supply

Ok guys, going for attempt (2) at soldering right now.. wish me luck :P

[tom66]

Re: Dell 3008wfp faulty power supply

I have a Dell 3008 WFP that does power on normally but the image is partially messed up as shown in the attached picture. I suppose this is not power supply related but if someone has any ideas what to fix I'd appreciate it very much.

I haven't opened up the display yet so I don't know if there's any visible indications of broken components. I have waited for the display to heat up but that doesn't make any difference. The colour of the lower part of the display responds to input signal but with a delay of several seconds. The problematic area is visible even when there's no input signal.

I suspect the lower LCD tab bonding is bad. It may or may not be fixable.

[fuus]

Re: Dell 3008wfp faulty power supply

Ok, next problem, I think I've lifted the pads? :/ the solder won't stick to the pads at all...

Images attached

[tom66]

Re: Dell 3008wfp faulty power supply

Pic I made for someone else but applicable to your problem.

[fuus]

Re: Dell 3008wfp faulty power supply

looking at the condition of those pads, and comparing them to mine, mine are no where near that bad. Do the pads need sanding, to remove oxidation?

[jetadm123]

Re: Dell 3008wfp faulty power supply

looking at the condition of those pads, and comparing them to mine, mine are no where near that bad. Do the pads need sanding, to remove oxidation?

If you've lifted the pads, then they are no longer reliable. What you have to do now is point-to-point wiring, which requires you to solder one end of a wire to the diode lead(s) and the other end of the wire to a non damaged solder pad (or point) as indicated in tom66's photo.

[fuus]

Re: Dell 3008wfp faulty power supply

OK, I've decided to take it in to my school teacher tomorrow who has more knowledge than me!

[heikkit]

Re: Dell 3008wfp faulty power supply

Thank you for the tip tom66. I took the display apart and tried applying pressure to and gently moving around all the bonding (4 on the left side, 12 on the top) in the display. Unfortunately I didn't see any response in the image. I also tried pushing the cable connections on the Tcon board without response.

I figured that the Tcon board might have bad internal connections so I gave it 10 minutes of oven treatment at 195 degrees. This attempt was futile as well.

At the moment I am inclined to think that it is the actual LCD panel that is faulty. However I find it quite strange that the image distortion covers exactly one quarter of the display height.

I'm open to any suggestions with repair tactics.

[tom66]

Re: Dell 3008wfp faulty power supply

It is the display panel - I said above.

It *may* be repairable.

You will need to take the LCD panel out and expose the ribbons.

Similar problem and fix:
http://www.youtube.com/watch?v=purk_SyiT44

It might be the side tabs in your case.

[heikkit]

Re: Dell 3008wfp faulty power supply

I did remove the metal cover in front of the panel and exposed the ribbons that connect to the screen (the picture shows the four ribbons on the left side). They seemed intact and I couldn't generate any effect in the image by pressing the ribbons. I couldn't figure a way to disassemble the display unit any further. Well, at least not in a way that allows me to put it back together.

[leapius]

Re: Dell 3008wfp faulty power supply

It does seem to me like a tape carrier bonding issue. Try getting some freeze spray and spray along each edge carefully whilst the screen is on to see if any changes occur at all. These ribbon tapes are stuck onto the panel using Anisotropic Conductive Film:

http://flipchips.com/tutorial/assemb...-introduction/

This video on the subject may be of interest to you:

http://www.youtube.com/watch?v=Qj51BkS9d-0

His channel is also very informative and worth watching.

Messing about with the tape carriers is VERY risky thing to do and can render your panel completely worthless so I might buy a replacement TCON board from aliexpress to rule that out. For such an expensive display I think it might be worth it. Either way this problem is either the TCON or the connection from the TCON to the panel itself. There could be an outside chance that the power to the TCON board is at fault but this can be ruled out with a multimeter.

[heikkit]

Re: Dell 3008wfp faulty power supply

Thanks for the info. I tried cold spraying all the ribbons connecting to the screen but there was no effect in the image. I also sprayed the connections coming from tcon board without results.

Maybe I'll try replacing the tcon board then. I couldn't find it in Aliexpress but it seems to be available at Buyqual.

[wuudi]

Re: Dell 3008wfp faulty power supply

Hi guys,

I successfully repaired my power connection thanks to this forum. But I fear I have messed up with the repair process. I have destroyed or hopefully just misconnected a cable. This is what i get. Any idea which connector i have misplaced, or did i kill the display?

[Adreitz]

Re: Dell 3008wfp faulty power supply

Hi, everyone.

I've got a 3008WFP that I bought refurbished in 2009. Last weekend, I too had the monitor suddenly power down while I was away from it and go completely unresponsive to the power button. Dell gave me the runaround on the phone and I couldn't find anywhere local that repairs monitors, so I decided to try it myself after finding this thread.

However, I'm currently having trouble with the disassembly process. I got the bezel off with some difficulty and plenty of nicked edges. I also removed the stand. But the instruction steps below make no sense to me and I can't get the back off.

6. Place the monitor flat on a table with the screen up.

7. Un-clip the back panel with the center divider still attached from the metal body of the monitor. The tire levers or screw driver will do.

I really don't see how the panel and internals are being captured by the plastic shell of the monitor. I see no clips except those that hold the black divider to the back shell. I've tried prying at the two corners on the right hand side and can get the inside part of the way out, but after a while I start hearing ominous cracking noises. Flipping the monitor with the screen down makes more sense to me, so you're not fighting gravity, but the inside is still captured and I can't remove it.

Based on a thread at HardOCP, I've also tried removing the divider by undoing about seventeen black screws visible from the front once the bezel is removed. I can get the divider separated on the top and the sides, but it seems to be captured very securely on the bottom center and I can't figure out how to get that location to budge at all. So I figured that was a lost cause and attached it again.

Can someone explain the process more clearly? Maybe provide some photos? Where are these clips that are mentioned and what do they look like?

Thanks,

Aaron

[Adreitz]

Re: Dell 3008wfp faulty power supply

Heck, yeah!! Monitor is FIXED. (At least for the time being.) D22 was indeed the problem and was completely shorted.

It turns out that you can't remove the inner assembly from the back shell in the way that I was trying to do it. There are no clips per se, but there is an aluminum shield on the right hand side of the monitor that hooks onto the back side of the center divider. The shield and the card reader assembly on the left side are the only things that hold the inner assembly in place once the stand is removed. I was bending this shield backwards partially in trying to pry the assembly from the shell on this side. Once I saw this, I attempted again to remove the center divider and eventually got it off with some elbow grease. After this, following the instructions was relatively simple.

There is a possibility that you might be able to get the inner assembly out without removing the center divider by working from the left side, where the card reader is. The instructions made me think that the circuit board for the card reader was attached to the case, but it is not, so you don't have to worry about ripping out a ribbon cable or something like that. The USB port components need to clear their respective holes in the case and this was the problem for me, though I didn't realize it. If the center divider isn't removed, the case has more rigidity in this area and I wasn't able to get the ports clear so that the whole assembly could rotate out.

I'm not very confident in my soldering skills, so I was nervous about working on the board, especially after reading about Fuus' difficulties. However, I didn't have many issues. It really did help to apply a bit of fresh solder to the iron to melt the preexisting solder on the board. I think this helped to provide greater effective surface contact with the iron to improve heat transfer. Maybe the fresh flux also helped. I set my iron to about 550F (according to the control dial, not sure how accurate it is), which worked fine for me. My solder sucker removed most of the solder from the pads, but there would always be a small amount left over that I couldn't get off. So I'd try to move the leads of the components to the centers of their respective holes using the soldering iron and then carefully use pliers to break the remaining solder connection between the board and the component leads.

Another issue that I didn't quite anticipate is that diode D22 is secured to a small heat sink using a bolt, with another diode on the other side of the heat sink. In addition to the nut, there are also several other small parts to take care of -- there is a small pad with a hole for the bolt in it that goes between D22 and the heat sink (probably a heat conductor/electrical insulator), and two plastic grommets that insulate the bolt head on one side and the nut on the other side from the diode mounting points. All of these little pieces, coupled with the surrounding components blocking easy access, meant that it took maybe five or ten minutes to get the replacement D22 mounted again so I could start soldering. The hardest part was starting the nut on the bolt shaft while also holding the bolt in place and trying to balance the board at an angle where the nut wouldn't fall off. Helping hands (human or otherwise) would make this easier.

The monitor went back together in about a tenth of the time it took to disassemble it. I did a quick power-on test before I put the case on to check that the replacement diode was doing its job. One of my friends helped me for a while in the disassembly and took some photos of the later stages that could be helpful. Let me know if anyone would like me to try to upload them (not sure if my new account will allow it).

Thanks to everyone for all of the info in this thread! It was very helpful and I never would have been able to do this on my own. Thanks especially to zen for diagnosing the problem and synatrol for the detailed disassembly instructions. This saved me a lot of money. Instead of spending $1250 for a new U3011 or several hundred for a commercial repair (not that I could find any shop able to do this, but just sayin'...), I spent about $78 in total on supplies -- I didn't already have a soldering iron.

It was crazy frustrating taking the thing apart, but very satisfying to finally fix the problem.

Thanks again!

Aaron

[synatrol]

Re: Dell 3008wfp faulty power supply

I'm glad you got it apart yourself. Reading step 7 now, after several months, is definitely no longer clear to myself without having the monitor half pulled apart again. And that is something I'm not keen on doing again.

[Adreitz]

Re: Dell 3008wfp faulty power supply

Heh, no kidding. With the labor involved, I don't think any reasonable amount of money would make me willing to do this for someone else. Thanks for checking in again!

Aaron

[hardwarexpert]

Re: Dell 3008wfp faulty power supply

I would just like to say a big thanks to this forum and all its members.

I successfully fixed my monitor upon reading the guide here and I'm over the moon seeing as I got the monitor for free.

It cost me £30 for the parts (a new soldering iron as well as the rectifier) and a boat load of patience but I got there.

To those who are about to embark on the mission of repairing their monitor, my tips are go careful on the removal of the front bezel and take your time. The metal feels like it wants to separate itself but its attached to a plastic surround on the back of the metal bezel. Secondly once you have the power board out and are ready to remove the big heatsink along with the two chips - I found I had to use a pair of long nose pliers to twist the metal support legs which attach the heatsink so they lined up with the PCB holes to be able to remove the heatsink from the PCB.