E228WFP display disappears

Okay so right now I have a resistor on R821 and on C808. The little square block on R821 was removed and the little brown block was removed on C808. Somehow, that made my monitor to work. Now knowing that this situation is dangerous, I'm going to buy the capacitor you told me about (2.2uf 16v Capacitor). So I remove the resistor I put on C808, and solder the 2.2uf 16v Capacitor on the C808 pads? Thanks again!

Replacing the 2.2uf 16v capacitor it may not make any noticeable difference but it does have a place in the circuit usually they are for smoothing start-up voltage spikes and also keeping the voltage consistent while running, much like a pressure tank.

Having two R821's(1 Mohm ea) is the same as one 2Mohm resistor. By increasing R821's ohms It will alter the circuit and may burn out other components that cannot handle that amount of power running through them. (capacitors can explode with too much volts running to them) the 16 pin PWM is rated for a max of 40 vdc.

I is apparent that some E228WFPc monitors degrade worse than others, the first two; by replacing with new R821 solved the problem but the third one it is the same problem but the replacement R821 must be more than 1 Mohm to solve this problem and still may only work for a year or two until the voltage gets high enough that  it once again develops the problem. I am trying to find the cause of the high voltages.

I appreciate comments and questions, Thanks to everyone that has helped so far.

Hello,

I have a E228WPFc as well, and less than a month after the warranty was over (bought it with a system, so I got stuck with the 1 year warranty instead of the typical 3 year, thanks Dell, way to stick it to the customers on that policy). I called anyways, and although they were really nice (and surprisingly without a hard to understand accent) they were unable to help considering this policy.

Funny thing is, I just had the HDD on the same system develop nearly infinite bad sectors, again, less than 1 month after the 1 year warranty, lost a lot of data (work related to boot), thankfully I backup regularly, so was able to retrieve most of it, BUT, that's a complaint for another thread..

Anyways, replying to this thread because I did all that I can gather was suggested as the final repair:

-Replaced SMC resistor with a much larger axial model, 1 mega ohm 5% (measured, was actually 1 005 00 ohm, not too shabby)

-Pierced holes in the white cover to allow further ventilation (although I didn't see that helping since air convection would allow it to flow from the bottom to the top, ie, under the white plastic from one side to the other, but no harm, so tried it anyways).

-Put a second rubber spacer in the other silk screened square.

So, final result, screen does the exact same thing. :emotion-9:

Perhaps this combined with your having replaced other parts is what's done the trick ?!

I checked out the suggested lcdrepair.us replacement model: http://www.lcdrepair.us/E228WFPc-inverter-power.html

Looks like this model has a completely different inverter section, so I imagine there were other updates / modifications made.

Well, thought I'd share my experience. If there are any other good, solid suggestions, I'd entertain the possibility of trying them out, since it bothers me like crazy to have spend so much for this otherwise very good looking paper weight.

If I had the money I think I would have purchased the extended warranty from the get go, but I don't, and still don't, I guess that's why I was looking for a good price on my system. But, as they say, you get what you pay for. So far my clone has been running fine for over 7 years now, and the monitor connected to it, over 10 years. Given it's age, you can consider how large this CRT is, and having gotten used to the LCD flat panel, it has been Very hard to switch back to my CRT

I think I need a vacation :emotion-59:. Knowing my current luck I think there will be :emotion-60: the whole time tho  lol

Replacing the 2.2uf 16v capacitor it may not make any noticeable difference but it does have a place in the circuit usually they are for smoothing start-up voltage spikes and also keeping the voltage consistent while running, much like a pressure tank. Having two R821's(1 Mohm ea) is the same as one 2Mohm resistor. By increasing R821's ohms It will alter the circuit and may burn out other components that cannot handle that amount of power running through them. (capacitors can explode with too much volts running to them) the 16 pin PWM is rated for a max of 40 vdc. I is apparent that some E228WFPc monitors degrade worse than others, the first two; by replacing with new R821 solved the problem but the third one it is the same problem but the replacement R821 must be more than 1 Mohm to solve this problem and still may only work for a year or two until the voltage gets high enough that  it once again develops the problem. I am trying to find the cause of the high voltages. I appreciate comments and questions, Thanks to everyone that has helped so far.

Actually, if he's replaced the C808, which is in parallel with R821, he's halved the resistance. The total value of 2 resistors in parallel is one quarter the total value of the two.

So, 1,000,000 ohm resistors in parallel = 500 000 ohms. If they were in Series (in a row), then the total would be 2 000 000 ohms.

Checked out RickyWii' posted schematics to verify:

http://www.scribd.com/doc/14955876/Philips-Chhudson8-170s8Fs00-Series

Page 22 of 122, section C2 for the R821 resistor. On that note, if you place a resistor on top of C808 and leave R821 there, then the same applies, you are effectively lowering the resistance of R821. Perhaps that is the key!? Unfortunately my circuit troubleshooting skills have significantly lowered since I finished school, so I really can't be of my assistance to figure out the problem.

I see Ricky Wii put a 500k on top of the C808, so that would make the same as putting a 750K instead of  R821...hmm

Anxiously awaiting some replies on this :emotion-5:

The total value of 2 resistors in parallel is one quarter the total value of the two.

Thanks  Frank06, I did not know that.

I have two of these monitors that have and had this problem.

The second one was purchased because of a mistake trying to repair the first, to repair the first one (And before The schematics were found).

The first one had different symptoms than the other:

1. Would work Fine for varying time (30/40 Minutes - 2 Seconds) and seemed Like An Overheating Problem.
2. Would Shut off Backlight Within 5 Seconds every time It was turned on.

I replaced R821 On both of these monitors and...........

1. Worked for 2 Months and it is doing it again, same as before.
2. Is still working Very Well

I am Doing some experimenting to see if A 976 Or + 953Kohm Resistor as R821 to see what it will do.

I am not paralleling R821 with another on C808 On both of my monitors R821 Was replaced with another 1 Mohm resistor

I posted pictures on an earlier post

I see Ricky Wii put a 500k on top of the C808, so that would make the same as putting a 750K instead of  R821...hmm

That makes sense with R821's (circuit Value) at 750K It would surely work, But as was said earlier that R821 is likely part of A shutoff circuit, and by altering R821's value it is just allowing it to still operate, overriding whatever is shutting it down. At first I hoped it would make some part obviously bad so I could just replace it and have a good monitor again.:emotion-7:

I am trying to find out how much less ohms will make it work, because if It will work at 750K when it is supposed to work at 1-M Then it is possible that replacing R821 with A 976K  it may work and if that does not I'll try A 953K.

And another Thing I found out :

The replacement Board 751G2244-2 Will fit this monitor If you notice where the 715G2594-1-4 board is mounted there are unused mounts toward the top of the unit to install the 715G2244-2 board pull off the mounts that are not used by the 715G22244-2 Board by bending and pulling on them. when installing the mounting screws in the never used mounting holes it may be a little stiff at first it is normal.

Here is one on eBay

• The Blue Circles are the mounts for 715G2244-2 Board.
• The Red circles are the mounts used by 715G2594-1-4 Board that must be removed When installing the 715G2244-2 Board.
• The Yellow circle is a holding mount that is compatible with both boards.

The plug on the 715G2244-2 is a little different and is black not white like the socket but it will still work.

Note: Sell your old board (715G2594-1-4) on eBay or somewhere to help pay for your new board, (and to give all of those who failed and want another chance:emotion-6:)

Any updates on how monitors are doing? I just picked up the same model as everyone describes here (E228WFPc) for $40. I'm use to resetting/resoldering points on mobo's and small areas, so that isn't an issue. I'm about to head to Radioshack tomorrow to pick up the parts, but was wondering what parts exactly are needed. I mostly deal with chipsets, ball bearing solder, wiring, ect...so resistors/caps are new for me.

My monitor is the same as most others, stays on for a random period of time, blacks out with the green power button still lit, power off/on and it comes back shortly. I can *barely* see the background image when the screen goes out.

So, what parts EXACTLY are needed, and where do they go? Just so I don't screw this up, as a few methods have been described in this thread.

Thanks a million!

I have been looking at a Dell E228WFP with the same fault as previous posters on this forum. It works for a few minutes and then the back light turns off. With the PCBs out of the case it runs for a little longer. Applying heat to the inverter board using a hair dryer causes it to turn off in about 5 seconds.

If you are after a quick test to see if your monitor is suffering from the R821 'resistor problem' then simply remove R820 (labelled 564), power up the monitor and heat the inverter board with the hair dryer. If it no longer turns off then R821 is probably your problem. I have shown the relevant section of the schematic below.

I have not had a chance to make appropriate measurements to determine a suitable replacement value for R821. Reducing it from 1M to 560K or 470K will certainly lower the error voltage being fed back to IC801. If anyone wanted to determine a suitable value empirically then I would suggest replacing R821 with a 470K resistor in series with a small 500K preset and determining the highest value that allows it to operate correctly when heated. I would then back this value off by about 10% and fit the nearest fixed value 0603 SMT resistor.

I have now carried out the above and R821 needs to be 470k to ensure reliable operation. If I had more time I would look into why this change is required....

Another E228WFP blanking out every 2 mins after using for several hours.

Tried replacing all capacitors and then it wouldn't last 5 mins before starting the blanking out problem.

I removed R821 and replaced with one 1meg resistor. Still had same issue.  

Then added a 2nd 1meg resistor in parallel with the 1st effectively making it a 500k resistor.  Seems to be working great.  Have had it running for several hours now....let's see how long this one lasts. Will keep fingers crossed !  

Thanks to all on this thread for the ideas !

a 500k resister has fixed mine, going on 30days of use 10+ hours of use daily.

bvq I have E228WFPc with this problem. However I think this model may have more than one power board. Mine's 715G2244-2. The parts don't seem to line up entirely with the schematic you provided, so I'm not totally confident that the resistors mention - R820 and R821 are the correct ones for this board.

Any guidance here appreciated.

Just do what I did. My monitor is still working. FYI new board (which does not have this problem) costs about $50, meaning even if you screw up it will cost you only $50.

Then added a 2nd 1meg resistor in parallel with the 1st effectively making it a 500k resistor.  Seems to be working great.  Have had it running for several hours now....let's see how long this one lasts. Will keep fingers crossed !

Adding a second 1M in parallel worked for me, too: I soldered a 1M surface mount resistor on top of the existing one at R821.  I'm no electronics guy, and man those things sure are tiny!  But the monitor has been running for 12 hours (without a screensaver) whereas prior to my hack job it would turn off the backlight within minutes of being powered on.

thanks to you experimenters!

E228WFP

Hi i have the above named monitor, i am experianceing the same problem as most, all i get is the green light, it occasionaly flashes the "DELL" boot screen, what can i do about this please, as i cannot afford a new one, much to my dismay it is an awesome screen!

Thanks

Great thread thank. Helped me loads.

Used this youtube video to figure how to open monitor, very similar to mine:

http://www.youtube.com/watch?v=5WLzdjYnbDE

Had same problem with 2 E228WFP monitors. Tried 470K resistor without 1Meg R821 but still had same problem.

Soldered 470K 1/4watt resistors in parallel with exisiting 1Meg R821. Covered resistor in heat shrink.

Effective resistance then 320K odd.

Both monitors working for past week without any problems now.