Dell 2209W - no power at all - stripped down but can't see anything obvious

[retiredcaps]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Capacitor C952 = 900V to 1800V rapidly cycling around (I had to test this a couple of times to make sure I wasn't misreading it!)

Your multimeter would not have survived if the voltage was really 1800V.

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

That's what I thought!! I tested it on some batteries this morning and the multimeter is fine.

So assuming some of those 'cycling' voltages are not accurate they at least indicate that the voltages on those points are not as they should be. Can anything be deduced from this? Is there anything else that I can measure?

[selldoor]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

What were you using for the earth/ground point and was the connection good
crocodile clamp is sometimes used to keep the ground probe in place.

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

I was usually measuring either side of a particular component as directed by previous posters. I took my time to make sure I was getting a solid contact with the solder or the leg of the component and retook the readings to make sure they came out the same.

[selldoor]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Ok -Can you re check the fusible resistors - power off - meter on ohms.

Then -Power on - 2 boards connected (or all if you can)- check the voltages at the two connectors.

Meter on VDC put black lead on nearest ground screw/hole and check each pin with
red lead post results - if the pins are labelled on the board give results as follows
CN1
Pin 1 24v Actual 24.2
Pin 2 5v Actual 4.9 etc etc

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

I've just tested and all the components starting with FR or F are measuring zero ohms.

I connected the two large boards but not the screen,the little controls PCB or the connector to the USB ports.

I measured the pins for each of the connectors as follows:

Connector near F851 and F852

1 = 770mV
2 = 770mV
3 = 770mV
4, 5 & 6 = soldered in a lump to GND
7 = cycling 0 to 1.7V
8 = cycling 0 to -33mV
9 = 0V
10 = cycling -1.1 to -2.1V

Connector on the opposite corner

1 = 0V
2 = cycling 1.4 to 3.6V
3 = cycling 0.2 to 0.6V
4 = cycling 0.2 to 0.6V
5 = cycling 0 to 0.2V
6 = cycling 0.2 to 0.6V
7 = cycling 1.8 to 3.5V
8 = 0V

Hope this helps!

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Hi All

I am just posting back here to say that my monitor is still in bits and I am wondering what to do with it.

I managed to get an identical model off eBay, it's a 2009 model so a bit older and was sold as 'not working' although after asking the seller it was listed as such just because it once showed a yellow line down the left hand side. It corrected itself and it has not appeared since. I now have it installed and it has been working perfectly.

So I am just wondering if there is anything I can do for my broken monitor. I know it's hard to fix complex problems by forum post but is there anything I should try or do I just give up on attempting it to fix it here?

If I give up on it then is it worth me keeping it in case my eBay 2009 version has a re-occurrence of the yellow line issue. I could then perhaps swap bits from one to the other. However I wouldn't know what to swap and if the source of the yellow line issue is on the main board then it's pointless as that is the bit that is broken on my broken monitor!

Any thoughts from previous contributors to this thread? Or indeed anyone reading?!

Thanks again
Ian

[Rtech]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Ian, the Yellow line is no doubt a Screen fault, so you could probably swap screens from the 'one in bits'.It is comparitively easy.

[selldoor]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

I suggest start again from scratch.
( Just say if you dont want to do this)
With it all connected up and a signal source (PC)playing a dvd is good, tell us what happens when
a, you plug it in
b, you press the power button.

What sounds, clicks/ pops/ squeaks etc
what is the power light doing from plug in to stable state.
I will go through the thread and pull out all the tests
suggested and as we go, perhaps others will chip in.

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

OK, that sounds good. Any chance the broken board can be fixed has it reached it's conclusion?

[selldoor]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Sorry -lost me already - I am talking about the old monitor not the new yellow line.
did you get some other boards for the old monitor. - just put together what you think are the best parts.

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Sorry cross post, my reply #90 was to post #88.

In reply to Selldoor:

I am not keen to do all the same measuring again as it takes time and I don't think we are learning anything new. If there are specific items that should be measured I can do those if it is going to be valuable.

In terms of the overall status that's very easy to describe as it has never changed from the first day it failed.

The PC was on and the screen went dead. The power light went out. No sounds were emitted at all. Ever since then the power light has never gone on, and the screen has never 'lit up' neither has it made any sounds.

From my basic take on it (and my high school electronics) it seems that the power supply circuitry is the source of the issue as the voltages all over the board are not constant but cycling all over the place with voltages not near what they should be. So whatever is taking the 240V AC into DC is borked.

Anyway, I appreciate the input and am open to ideas.

Ian

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Sorry -lost me already - I am talking about the old monitor not the new yellow line.
did you get some other boards for the old monitor. - just put together what you think are the best parts.

Yes, cross post confused things. I have the broken monitor (the original in this thread) and the recent purchase from eBay which allegedly had a yellow line on it at some point. It is working fine right now and I was only mentioning that in case it would be possible for me to swap useful bits from the broken one in the case that the yellow line ever came back.

[selldoor]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Yes - as Rtech said the panels may be the same- you will need to check the label
affixed to each panel and see that it is EXACTLY the same model number and that the connector is the same. They are not always even in the same model monitor.

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Yes - as Rtech said the panels may be the same- you will need to check the label
affixed to each panel and see that it is EXACTLY the same model number and that the connector is the same. They are not always even in the same model monitor.

OK, that's good. I'll check.

[Batz]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Sorry cross post, my reply #90 was to post #88.

In reply to Selldoor:

I am not keen to do all the same measuring again as it takes time and I don't think we are learning anything new. If there are specific items that should be measured I can do those if it is going to be valuable.

In terms of the overall status that's very easy to describe as it has never changed from the first day it failed.

The PC was on and the screen went dead. The power light went out. No sounds were emitted at all. Ever since then the power light has never gone on, and the screen has never 'lit up' neither has it made any sounds.

From my basic take on it (and my high school electronics) it seems that the power supply circuitry is the source of the issue as the voltages all over the board are not constant but cycling all over the place with voltages not near what they should be. So whatever is taking the 240V AC into DC is borked.

Anyway, I appreciate the input and am open to ideas.

Ian

I'm most interested if anyone has any comments on my post above.

Ian

[CroTech]

Re: Dell 2209W - no power at all - stripped down but can't see anything obvious

Have this one laying for some time now... The first thing when I opened it I noticed that it has the same PCB as the one in this thread.

The board looked OK except the LD7575 was severly burned so I unsolder it and cleaned the PCB with alcohol, bought 5 replacement LD7575 ICs and soldered a new one.

Put it to the test and voila, had smoe sparks and grey/whiteish smoke coming out of it.

All the fuses seem to be OK, the capacitors seem to be okay, but the LD7575 suffered AGAIN!

What should I be looking at?