Dell 2005FPW Issues

[zplizzi]

Hi

I've been having similar troubles with my Dell 2005FPW as many other people here seem to be having also. When I first power it up cold, usually the backlight will come on and the display will work - but the image is completely garbled because all the pixels will swipe up and down the screen randomly. I don't really know how to describe it. However, this will go away after about 30 seconds, and the display will work fine. If it is turned off and back on, however, it will come on for the standard .2 seconds and shut off, like many other people noticed. Sometimes, it will come on and emit a high pitched hum that will sometimes go away with a power off, but often will lead to a cycle of the .2 second power, then reboot, and loop forever until the power is pulled.

I have opened the monitor up and inspected for bad capacitors - I've had that issue before in my motherboards However, none of them seem obviously bad. I can replace them, but there's tons of them on both the inverter/power board and the video board, and I don't know which to replace.

Sorry for the long posting - it's my first post here Pictures are attached of both sides of the power board and the front of the video board. I'd be happy to read off and part numbers you need if they aren't visible in the pics.

[momaka]

Re: Dell 2005FPW Issues

Looking at the picture of the video board you posted, note the slightly darker area on the board on the lower-right corner around the linear regulators. That slightly darker are is heat discoloration and it's very possible that the capacitors in that area have gone bad or are on their way out.
I would suggest to replace those first and see if that cures the problem.

It seems like the power supply has Sam Young capacitors - those aren't overly horrible, but if you're buying new caps online, you might as well get replacements for those too. The only exception is the big high-voltage capacitor - this one does not need to be replaced since it rarely fails.

If you're not sure what replacements to get, post each capacitor's brand, series (usually 2 or 3 letters), capacitance (uF), voltage (v), and size (dia. x height in mm).

[zplizzi]

Re: Dell 2005FPW Issues

Ok - thanks. I know that you guys are always adamant about using certain kinds of capacitors, but is it ok if I replace these with standard ones just to try it? I have tons of radio-shack type capacitors in those sizes that I could put in just to see if it fixes the problem, instead of waiting for digikey to ship me new ones. I'd then replace them with the better ones when I get them. Or would it be better just to be patient?

Also, do I need to replace the ones that are not vented?

Here's the listing for the caps in that section of the video board:

2x 220uf, 16v, 12x7mm, T3C series
3x 22uf, 25v, 11x5mm, T4C series
2x 470uf, 16v, 12x8mm, T5A series
6x 100uf, 16v, 11x5mm, T2C series

I don't see a brand name on them, and I don't know the logos, so I attached a pic.

I know my way around digikey a bit, but if you could tell me what to buy, that would be great.

Again, thanks for all the help.

[jetadm123]

Re: Dell 2005FPW Issues

They look to be Sam Young caps. If you need to "try" to replace one or two caps, then I would say go ahead and try it. However, your looking at replacing over a dozen caps. I don't know what your soldering skills are like, but the logic boards tend to be smaller and the solder pads easily peel away due to excessive heat. Also, are the replacement caps you have been removed from other equiptment? If yes, you might be replacing questionable caps with questionable used caps. You probably would be better off ordering new caps. That way, you have good quality caps installed, or at least a good starting point if the new caps don't work.

[momaka]

Re: Dell 2005FPW Issues

Ok - thanks. I know that you guys are always adamant about using certain kinds of capacitors, but is it ok if I replace these with standard ones just to try it? I have tons of radio-shack type capacitors in those sizes that I could put in just to see if it fixes the problem, instead of waiting for digikey to ship me new ones. I'd then replace them with the better ones when I get them. Or would it be better just to be patient?

You can try it if you want to, but there's no guarantees it will work. This is the reason why most people here don't encourage even temporary recaps with general purpose caps - there's just no way of knowing whether the recap was done wrong, whether the general purpose caps weren't good enough, or whether the monitor has other issues.
For people who don't have much soldering experience, a recap could take a substantial amount of time and effort and when their recap doesn't work because of marginal replacement capacitors, they may get frustrated and just junk the device.
With that said, I'll leave the decision to you if you want to try it. If you have some experience soldering and this won't be a hassle, then feel free to try. But again, no guarantees.

Before changing the caps, though, I think it may actually be a better idea to check the voltages on those regulators first. Start by getting a datasheet for each linear regulator so you know what voltage it needs to output, then check the voltages with a multimeter. If you can't find their datasheets, post the part number of each linear regulator here. I see at least 7 on the video board - 4 of them are in the lower-right corner.

As far as the caps, I've never seen that brand before either. Only 1 Elna I recognize. Still, all of them are likely just general purpose rated for 105C. I guess the Radio Shack *might* work (or at least they won't be that much worse).

[zplizzi]

Re: Dell 2005FPW Issues

Ok - I tested the linear regulators, and all five on the right side of the board seem to work as expected as per the datasheets. They were also all warm when it was plugged in. The other two on the left side did not have input power, so I assume that is because the lcd is not plugged in? I just hooked the two boards together and tested - so the lcd is not running, nor are any video cables plugged in.

I will probably end up trying some of those radio shack caps - they are new, not used, luckily In the meantime, what caps should I order off digikey? Just standard caps with those uf and voltage ratings? Or do I need low ESR caps?

By the way, I found the service manual with the schematic and part #'s and everything. It's at http://www.keepandshare.com/doc/2714...m-5-0-meg?da=y right now... I don't know how long it will stay there For some reason I can't upload it - if someone else wants to, for the others out there when the link goes bad, go ahead...

Thank you guys so much for the quick responses.

[PlainBill]

Re: Dell 2005FPW Issues

Ok - I tested the linear regulators, and all five on the right side of the board seem to work as expected as per the datasheets. They were also all warm when it was plugged in. The other two on the left side did not have input power, so I assume that is because the lcd is not plugged in? I just hooked the two boards together and tested - so the lcd is not running, nor are any video cables plugged in.

I will probably end up trying some of those radio shack caps - they are new, not used, luckily In the meantime, what caps should I order off digikey? Just standard caps with those uf and voltage ratings? Or do I need low ESR caps?

By the way, I found the service manual with the schematic and part #'s and everything. It's at http://www.keepandshare.com/doc/2714...m-5-0-meg?da=y right now... I don't know how long it will stay there For some reason I can't upload it - if someone else wants to, for the others out there when the link goes bad, go ahead...

Thank you guys so much for the quick responses.

No input power for the regulators is unusual. What are the identifier numbers for them?

PlainBill

[zplizzi]

Re: Dell 2005FPW Issues

They are:

U502 - LD1117S18TR STM SOT223 R/TP
U506 - RC1117S-33 SOT-223 TP 1A 3.3

According to the datasheets, the first is a 1.8v and the second is a 3.3v regulator.

I just rechecked it and they still have no input or output power.

[PlainBill]

Re: Dell 2005FPW Issues

They are:

U502 - LD1117S18TR STM SOT223 R/TP
U506 - RC1117S-33 SOT-223 TP 1A 3.3

According to the datasheets, the first is a 1.8v and the second is a 3.3v regulator.

I just rechecked it and they still have no input or output power.

OK, that's not that unusual. They are for the USB hub. Power comes from U501, a power switch. Power enters U501 on pin 4 and is controlled by pin 5. And pin 5 is controlled by the 'B' connector on the USB cable from the computer. So it's working as designed, and not the cause of any problems.

PlainBill

[zplizzi]

Re: Dell 2005FPW Issues

Good - thanks. So should I just go ahead and order standard caps off digikey, or do I need the low ESR ones? Any particular brand or anything to know that they are good quality?

[PlainBill]

Re: Dell 2005FPW Issues

Good - thanks. So should I just go ahead and order standard caps off digikey, or do I need the low ESR ones? Any particular brand or anything to know that they are good quality?

There are a number of brands and series that are good quality. My personal preference is Panasonic FM, FR, and FC. FC is probably overkill for this application, but I doubt the extra cost will be significant. The 'Whch Caps Should I Buy' thread in the FAQ lists other reliable series.

This post gives a method of selecting suitable caps.

PlainBill

[jetadm123]

Re: Dell 2005FPW Issues

Oops! Looks like they're using Samwha RD series general purpose 105 deg C caps and not Sam Young as I had mentioned earlier.

[Toasty]

Re: Dell 2005FPW Issues

Here's the schematic. I mentioned the PDF upload problem -many months- ago. Deaf ears I suppose.

I uploaded to my site then to here. That type of attachment works, just not from your computer to here.

[zplizzi]

Re: Dell 2005FPW Issues

Well, sorry for the very long delay guys... i won't give excuses because I don't have any

I finally did replace the bad capacitors on the monitor. It seemed to work, but as I was putting the monitor back together, one of the little traces on the right side of the screen got partially cut. Therefore, the bottom fourth of the screen does not work - it only echoes colors from the rest of the monitor.

I assume I killed it and there's no way to raise the thing back from the dead.. am I right, or is there some way to fix the trace?

Thanks so much!