W241D (W240D) flickering Problem

[Yetanfou]

Re: W241D (W240D) flickering Problem

Yes I too have it in front of window. When the sun shines in and it gets hot, flickering sometime resumes. I would love to permanently repair it, as it is a nice monitor, I can only set resolution to 1024x768, any higher and it flickers constantly unless it is really cold.

Replacing the two 100uF/16V SMD capacitors marked by red circles in Leontius' post earlier on this page solved the problem for me, after having gone through some earlier, partly successful (but in retrospect probably futile) steps.

I measured the capacitance and ESR for those caps I removed. One measured at 76uF/7 ohm, the other was 82uF/13 ohm - in other words, they were past due. As I did not have any 100uF capacitors handy I replaced each by two 47uF/25V (axial electrolytic) in parallel. The ESR for the replacements (in parallel) was 0.07 ohm.

I now run the monitor without the fan I built in the back. The hole behind which the fan lived is still there (with a grating in front to protect the inner workings) so passive cooling is improved over the original.

https://www.badcaps.net/forum/attach...1&d=1453656621

The thing has not flickered yet, not even when displaying 10 terminal windows crammed with small-font content. While this would work initially, it soon required the fan to be stable. Lately it jumped around even with the fan at maximum speed. Now, it just works... or should that be 'for now...' - time will tell. There are sure to be other bad capacitors on the board, they just don't have as visible an effect on the workings of the monitor.

For those interested in installing a fan in this monitor, you can get 12V from the power supply, just look at the unpopulated connector for which lines to use.

[Dodgexander]

Re: W241D (W240D) flickering Problem

I have exactly the same problem with this monitor. I've tried replacing the two caps mentioned in the thread earlier but it hasn't fixed the problem. After a while the monitor continues to flicker.
Is there a method to diagnose this fault and fix? Thanks for any help.

[Chriscaps]

Re: W241D (W240D) flickering Problem

I had the flickering from the bottom issue, replaced the 2 caps by the 2 regulators shown in Leontius' post and the monitor has been flicker free for several days, thanks.

[Leontius]

Re: W241D (W240D) flickering Problem

Try replacing the two capacitors marked with yellow circles on this picture:
http://i60.tinypic.com/acei54.jpg


They can be replaced with electrolytic ones. Worked for me.

I can't edit my post anymore, and Tinypic has removed the picture, so I am uploading it again, because after 6 years the problems have reappeared. Fortunately, we know the solution now

[Stefan Payne]

Re: W241D (W240D) flickering Problem

I can't edit my post anymore, and Tinypic has removed the picture, so I am uploading it again, because after 6 years the problems have reappeared. Fortunately, we know the solution now

Use through hole Caps and bend the legs, solder them.

I did that with mine and "accedentally" used Polymer Caps.
Might be worth a try.

[Stefan Payne]

Re: W241D (W240D) flickering Problem

and you might want to add some form of heatsinks to that as well...

I myself haven't used the W241D much in recent years.
Just because I got better, more modern Options...

[Leontius]

Re: W241D (W240D) flickering Problem

This is how the Jamicon 216C2(M) 105 ℃ 100 μF 50 V capacitors I mentioned in this post look like after 6 years of everyday usage for about 10-12 hours per day. As you can see, they are clearly bulging, but exchanging them with fresh ones solved the problem once again.

I myself haven't used the W241D much in recent years. Just because I got better, more modern Options...

I am still using it, because after 12 years it still works perfectly.

[cappy67]

Re: W241D (W240D) flickering Problem

hello badcaps experts,

this thread is already old, as is my W241D.
Yesterday I gave a repair of this flickering device another chance.

I found this austrian thread (in German) about the issue, where some guys reported to have replaced caps, added cooling devices etc., all that already years ago.

And then recently (in 2020) another person discovered the voltage regulator in question (the upper one of the two LM1024 on the main board) is missing any HF blocking capacitor. With him I share the experience that in quite some cases the internal inductance of typical dielectric capacitors of e.g. 10uF is too high to keep such regulators from oscillating. And even small amplitude parasite oscillations are heating the semiconductors up much more than a pure DC operation !

I added a small, ceramic capacitor of 1nf between input and mass (those are the two pins on the frontside).

And now I'm using the monitor for hours now on full resolution, including 2 hours video, and no flickering showed up !

good luck !

[Yetanfou]

Re: W241D (W240D) flickering Problem

Well, I hinted that I'd be back last January 2016... and here I am again with a flickering W241D. In other words, the repair lasts for around 5-6 years before it needs to be repeated. That hint about the missing HF blocking capacitor looks interesting so that will be my first approach, more later...

[Per Hansson]

Re: W241D (W240D) flickering Problem

A belated thanks to the both of you for visiting Badcaps.net!
Be interesting to hear about the improvement the extra bypass cap can make

[Techami]

Re: W241D (W240D) flickering Problem

Hi, same like everyone here, I have problems with my w240d, I replaced the capacitors(those 100uf16V close to voltage regulators too) on the motherboard and power supply many times.

But now problem is with digital ports, on hdmi after some time the monitor turns off by itself. Need use power switch in back to turn it on if i use front touch button it's starts but have artefacts (most of the green lines) but OSD screen works fine and sound too.
With the dvi connected to the computer same problem monitor turning off alone only difference is that with DVI connected can't turn on monitor at all, power switch in back not help power led not even turning on, have to disconnect the DVI cable to start the monitor, but with VGA port everything is fine. Can't even start monitor when is cold(with dvi cable connected).
What can be broken that only digital connections have problem, what is this chip U301 close to dvi/hdmi port? Should I replace all these capacitors, even 10-47uf?

[Per Hansson]

Re: W241D (W240D) flickering Problem

+5v is sent from the computer graphics card via the DVI or HDMI cable to power the small i2c chips that contain a eeprom with supported resolutions etc even when the monitor has no external power.
Check that this actually works properly, it could be that the EDID data has been corrupted too, you can use something like Entech Taiwan's Monitor Asset Manager to read it: https://www.entechtaiwan.com/util/moninfo.shtm

[Techami]

Re: W241D (W240D) flickering Problem

Used this program but with vga connection it reads EDID so maybe this is ok.
But today is hot and now played @1920x1200 native resolution(VGA connection) and monitor turned off(most time i use 1440x900 in VGA conection).
Last days power supply burned of this monitor, big capacitor 450v 100uf and VIPer22A (ic500) chip, but replaced and started ok, and because of this I tested digital connections before just used low resolution 1440x900 with VGA connection.
When monitor is turned on voltage coming to LM1084-33 is 4.72-4.75v but when i turn off monitor with front touch power button this voltage jump to 7.5v I don't know if this is normal for this monitor, didn't check this before.