DELL 3008WFP repaired!

[AlexAnd]

As more and more owners getting their 3008WFP dead these days, I would like to give a hint. During long working periods high temperature inside turns isolation of cable (between main board and LCD controller) to very frail one. Then, it flakes away, allowing bare wires to connect. Short circuit (in most cases) blows the fuse (F2 on LCD controller board) which can be easily mended. But repairing the cable itself isn't a simple task. Here the example: https://www.badcaps.net/forum/showth...008WFP&page=13. My choice was eight shielded twisted pairs, taken from USB3.0 cable. Result was just awesome - no noise at all. Monitor became as a new one. Just solder all up, carefully isolating pair shields by PTFE-tape (you should make each shield connected with each third wire - also coloured - it is a local ground, I guess). So - no other wires are needed. But keep all factory shielding measures on their places! I'm sure they should be there.

[plecak]

Re: DELL 3008WFP repaired!

hi.
Could you please help me with my dell 3008wfp. the cable between main board and LCD controller the one with isolation flaking away. I will attempt to repair it using your method. could you tell me if your L2 fuse on the lcd steering board looked like mine? I am not sure that it is blown, i can see bare copper wires but it looks just like L1 next to it which suppose to be fine. Where I can buy a P220(L2) fuse from? Please see attached pictures thanks hope you can help.

[3d0]

Re: DELL 3008WFP repaired!

Where I can buy a P220(L2) fuse from?

P220 is an inductor, not a fuse, they don't fail that often.
You can test it with a multimeter easily.

[bammbammfran]

Re: DELL 3008WFP repaired!

I have repaired a lot of 3008s in the last 4 years and this issue does happen but only on rare occasion
It is not the most common issue

to plecak --The copper wire is supposed to be visible on this part
And, as 3d0 noted, that is an inductor and if that would have failed, you would have a lot of other problems

[Lumberjack777]

Re: DELL 3008WFP repaired!

Right; those are inductors. And if he doesn't know the difference between those and a fuse he better be careful when working on that monitor.
plecak, I'd probably do a little reading on board designators, and read some threads out here.

But since this thread was brought back up, I do have a question on a Dell 3008WFP main board I am currently testing.

I was testing voltage regulators and I tested a part labeled -- AK25P
I can't seem to find that exact datasheet. I believe its an adjustable regulator.
Here's the voltage readings.....

1. 0v
2. 2.28v
3. 3.28v

With the input voltage being 3.3v; how can the center tab be 2.28v ? (Fixed or adjustable. Unless I'm missing something)

[bammbammfran]

Re: DELL 3008WFP repaired!

can you post a picture of the AK25P and where it is on the board then I can take a closer look at one here

[Lumberjack777]

Re: DELL 3008WFP repaired!

can you post a picture of the AK25P and where it is on the board then I can take a closer look at one here

OK, I don't have my camera here. But I found one sold on eBay, but the pic doesn't exactly show it. It's in the area circled in red, behind the 4 little caps. AK25P

[bammbammfran]

Re: DELL 3008WFP repaired!

That is an sot223 2.5v 800ma fixed voltage regulator
I checked readings on a working one and I get almost the exact same that you get. My board works fine even though it is reading below 2.5
so this may not be your issue

what is the issue with you unit ?

[Lumberjack777]

Re: DELL 3008WFP repaired!

Thanks for checking. I'm amazed it works with readings so far below spec. (2.28v vrs 2.5v)

The symptoms vary. One time it was just a blue screen. Next time it showed the screen and detected vga. Then blinked off. It varies, but never really turns on fully. But it's really close. I suspected bad caps at first. I did a quick check with an ESR meter and they seemed within specs. Though some were in parallel. I'd have to desolder so many caps just to check them all. I was hoping it was that voltage regulator.

And one other thing. Once it showed the picture for a few seconds. Blinked off. But I could see a picture with a flashlight. The next time it didn't have a picture with the flashlight. It seems to vary each time I try and turn it on.

[AlexAnd]

Re: DELL 3008WFP repaired!

hi.
Could you please help me with my dell 3008wfp. the cable between main board and LCD controller the one with isolation flaking away. I will attempt to repair it using your method. could you tell me if your L2 fuse on the lcd steering board looked like mine? I am not sure that it is blown, i can see bare copper wires but it looks just like L1 next to it which suppose to be fine. Where I can buy a P220(L2) fuse from? Please see attached pictures thanks hope you can help.

F2 is a much smaller thing. It should give almost as little as ~0ohm if OK as I remember. I bought simple glass-covered one for the same power, broke it, got a wire from it and soldered this wire right over the blown F2. Best way, I think, but requires good eyes. Although, firstly, you should check - is your monitor switching on normally (led) but no image on screen? Secondly - check F2. If it's gone and you can see bare wires on that LCD contr. cable (you do) - this is a same issue as mine. So, you can buy a USB3.0 cable, tear pairs from it and do the job. Not so simple but possible - you can ask me anything about it. I'm sorry, but no shots I took while mending my 3008wfp. To disassemble it - the most terrible challenge here - I'll hardly go through it again, so there will be no photos, sorry.

[bammbammfran]

Re: DELL 3008WFP repaired!

To Lumberjack:

Sounds like maybe a power issue.
Lets try basics
disconnect all input sources and usbs
Remove the two plugs that lead to the controller board in the pictures .
Then power the unit up and see if you have 24 volts at the inverter fuse in the other picture (pencil is pointing to it). then check to see if the screen is glowing . This will verify power to the inverter and will show if the inverter is working.

If that is ok
connect only the small connector to the controller board. now turn it on and check for 18 volts at both sides of the fuse at F1 on the controller board (pencil is pointing to it) At this point you should see a full solid color cycling screen

if that is ok
plug an input source into the last known input that the unit was using and recheck the 18 volts on the controller board

[Lumberjack777]

Re: DELL 3008WFP repaired!

Thanks bammbamm. Sorry I didn't get back sooner. I had a distraction known as employment that kept me from responding.

Those look like excellent checks to make in the future. I should back up a little and tell you that I KNOW it's the main board. I swapped a board from one with a cracked screen and it worked perfectly. So I decided to tackle this main board that's defective to use in a future monitor once this is fixed. I actually have 4 bad main boards. 2 color cycle endlessly. This one varies, but occasionally shows the picture. I can't remember the problem with the 4th one.
But this one is so close to working I just need to find the problem. I'm going to take out the caps in parallel and test them. At this point I'm thinking it's a bad cap out of the tons of caps on that board. Thanks a LOT for all your help

[bammbammfran]

Re: DELL 3008WFP repaired!

I assume that you checked all the voltage regulators ?? There are a lot of them !!
I doubt it is caps.. I have seen these work with a few bad ones.

assuming the t-con and screen are ok- You should get 5 color screens with the 30 pin disconnected Bk-W-R-G-Blue
if not, the 20 pin connector might be a place to start to backtrack from