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Old 08-12-2010, 06:36 PM   #21
peterfares
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Default Re: Dell 2007WFP Won't Power On

The capacitor says 47uF 25V on it. Would it be ok to replace it with a 47uF 16V I have lying around? Also does anyone know if the monitor should start without the USB board in place? Because it doesn't.
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Old 08-12-2010, 06:41 PM   #22
retiredcaps
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Default Re: Dell 2007WFP Won't Power On

Quote:
Originally Posted by peterfares View Post
The 3A fuse shows 2000 ohms resistance. Is it good or blown?

Also the voltage regulator on the USB board is showing the same resistance as the one that is supposedly fried.

EDIT 2: I was able to scrape that gunk off the "blown" voltage regulator and it came off fine. The part doesn't appear to be damaged.
A good fuse should read 0.3 ohms. Your 3A fuse is bad at 2000 ohms.

Post another pic of the "blown" regulator. A reading of 5 ohms suggests it is shorted. The only way to know 100% is to measure it out of circuit so that other components are not affecting the reading.
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Old 08-12-2010, 06:44 PM   #23
retiredcaps
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Default Re: Dell 2007WFP Won't Power On

Quote:
Originally Posted by peterfares View Post
The capacitor says 47uF 25V on it. Would it be ok to replace it with a 47uF 16V I have lying around?
Generally when you replace caps, it should be the same uF and voltage. You can put in the lower voltage cap IF you know 100% certain that it sits in a path where the voltage never exceeds 16V. So if you knew for sure, that this cap sits in the 12V circuit, you can use the 16V cap.
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Old 08-12-2010, 06:48 PM   #24
peterfares
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Default Re: Dell 2007WFP Won't Power On

Does radio shack carry fuses? I can only find 250V fuses. Does the voltage only mean the maximum voltage?
They appear to only have the glass fuses and the blade fuses.

Also the "blown" regulator looks totally fine with the crap scraped off.
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Old 08-12-2010, 06:59 PM   #25
retiredcaps
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Default Re: Dell 2007WFP Won't Power On

Quote:
Originally Posted by peterfares View Post
Does radio shack carry fuses?

Also the "blown" regulator looks totally fine with the crap scraped off.
You will find a better selection at digikey.com. Shipping from them is around $2.50 USD from what other members report here. Digikey also sells caps as well.

Again, a reading of 5 ohms suggests that it is shorted (bad). Only way to know is to test out of circuit.

edit: With all that crap scraped off, what is the part number on the chip?
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Old 08-12-2010, 07:03 PM   #26
peterfares
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Default Re: Dell 2007WFP Won't Power On

It is a little hard to make out but it appears to be 960T65.

Also is it possible to use the blade fuse or would that not work?
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Old 08-13-2010, 08:41 PM   #27
peterfares
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Default Re: Dell 2007WFP Won't Power On

YES!
I replaced the 3A fuse with a 3A tube fuse from RadioShack and the monitor works!

Thanks for all your help!
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Old 08-13-2010, 08:59 PM   #28
jetadm123
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Default Re: Dell 2007WFP Won't Power On

Great job!! It wasn't as bad as you thought it might be.

Was that "gunk" covering the so called "blown" regulator electrolyte from the the cap? Is so, make sure you clean it up with distilled water and Qtips because it is corrosive.

I'm still a little puzzled how shorting out the 12 volt output affected the logic board so badly. Maybe you should use a 2A fuse instead of 3A.

Again, good work!
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Old 08-13-2010, 09:02 PM   #29
peterfares
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Default Re: Dell 2007WFP Won't Power On

I believe the stuff on the regulator was from the capacitor, there is a little bit of it all around that capacitor. Do you think it is going to go out soon?
Maybe the capacitor has nothing to do with what I did and is just a coincidence? I already put the whole monitor together without cleaning it up I'll have to do that some other day.
I also got some annoying scratches under the Dell logo trying to figure out how to open the damn thing.
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Old 08-13-2010, 09:08 PM   #30
jetadm123
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Default Re: Dell 2007WFP Won't Power On

If that cap is leaking, it would be wise to replace it ASAP with a low-esr cap.
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Old 11-10-2010, 10:54 PM   #31
freddy314
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Default Re: Dell 2007WFP Won't Power On

Dell 2007WPFB went blank. No indications that it's powered.
And I didn't do anything - just read the news

Can't figure out how to open the back cover for a quick fuse check.
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Old 11-10-2010, 11:40 PM   #32
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Default Re: Dell 2007WFP Won't Power On

UPDATE:
opened the box
found no fuses. No quick fixes like loose connector or so.
Looks like 2.5 years old DELL monitor is going to the recycling bin.
No more DELL for me thank you.
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Old 11-10-2010, 11:46 PM   #33
retiredcaps
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Default Re: Dell 2007WFP Won't Power On

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Originally Posted by freddy314 View Post
found no fuses. No quick fixes like loose connector or so.
I have opened 17 or 18 monitors and every one has at least one fuse on it. However, it may not be your problem.

If you are giving up, then post it on craigslist or something like that. Others will want a chance to fix it.

Last edited by retiredcaps; 11-10-2010 at 11:48 PM..
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Old 11-10-2010, 11:53 PM   #34
freddy314
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Default Re: Dell 2007WFP Won't Power On

retiredcaps,
thanks for the quick reply!
Will try tomorrow to locate the fuse one more time.
Could you please give me an idea where it could be?
Fuse is the only thing I possibly could "fix".
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Old 11-11-2010, 11:32 AM   #35
freddy314
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Default Re: Dell 2007WFP Won't Power On

Found and checked the fuse - OK.
It's beyond my capacity.
===
IF anybody need this monitor in Calgary - you welcome to pick it up.
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Old 11-11-2010, 01:11 PM   #36
Diablo_Rojo
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Default Re: Dell 2007WFP Won't Power On

Just in case you have not,check warranty status of your monitor. I see many with a 3 year warranty and you said 2.5 year old Dell. I just hate to see it end up in a garbage fill.
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Old 11-11-2010, 01:39 PM   #37
freddy314
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Default Re: Dell 2007WFP Won't Power On

I checked paperwork - 3years warranty. But I was wrong in the monitor's age - it's 3 years and 4 months.
Thanks for the idea anyway, I was sure it's 1 year warranty.

Anyway I have somebody from this forum interested in taking it.
I hope it will be easy fix for him!
I already researching for a new RELIABLE monitor.

Last edited by freddy314; 11-11-2010 at 01:56 PM..
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Old 01-22-2011, 11:09 PM   #38
core2kid
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Default Re: Dell 2007WFP Won't Power On

Sorry to bring this old thread back to life but I'm having a similar problem.
I have a second 2007WFP which will only flash the power and <- continuously. I replaced every board with a known good one and came down to the conclusion that the USB hub board has a fault in it. I broke it down even further and figured out that if I bend pin 3 out of the way, the monitor powers on but I don't see a picture on it. Any ideas?

Pin 3 is:
If you take peterfares picture below
http://www.badcaps.net/forum/attachm...8&d=1281651994

take the 12 pin connector at the bottom. The shown pin all the way to the left is pin 2. The one below it is pin 1. The one to the left of that is pin 3.

If you all need any pictures let me know. Thanks for all your help.
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Old 01-23-2011, 07:43 AM   #39
PlainBill
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Default Re: Dell 2007WFP Won't Power On

Quote:
Originally Posted by core2kid View Post
Sorry to bring this old thread back to life but I'm having a similar problem.
I have a second 2007WFP which will only flash the power and <- continuously. I replaced every board with a known good one and came down to the conclusion that the USB hub board has a fault in it. I broke it down even further and figured out that if I bend pin 3 out of the way, the monitor powers on but I don't see a picture on it. Any ideas?

Pin 3 is:
If you take peterfares picture below
http://www.badcaps.net/forum/attachm...8&d=1281651994

take the 12 pin connector at the bottom. The shown pin all the way to the left is pin 2. The one below it is pin 1. The one to the left of that is pin 3.

If you all need any pictures let me know. Thanks for all your help.
I would want to see pictures of YOUR board, good clear pictures of both top and bottom. That board is not only the USB hub board, it is the power input board.

PlainBill
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For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
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Old 01-23-2011, 10:03 AM   #40
retiredcaps
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Default Re: Dell 2007WFP Won't Power On

Quote:
Originally Posted by core2kid View Post
If you all need any pictures let me know.
1) I echo what PlainBill says. We want to see pictures of your board.

2) Check the voltage regulators (marked U) and diodes (FD) for shorts (especially FD3 and FD4).
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