LCD Desktop Monitor Fading to White, then Black
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From: saber850 on 3 May 2010 11:09 On May 2, 10:50 pm, Jeff Liebermann <je...(a)cruzio.com> wrote: > On Sun, 2 May 2010 17:58:59 -0700 (PDT), saber850 <saber...(a)yahoo.com> > wrote: > > >If it is the invertor or the power supply circuit, would either be > >worth repairing/replacing instead of replacing the entire monitor? Is > >there any part of an LCD monitor whose expense would not justify its > >replacement, and to simply replace the monitor as a whole? > > The Samsung SyncMonster 204/214 is all one big board. There are > replacement boards available on eBay but they tend to have the same > problem that you're trying to fix. > > Sending the monitor to the recyclers for such a simple problem will > surely bring down upon your head the wrath of all repairmen, > ecologists, and toxic waste handlers. To maintain your karma, you > must at least make an attempt at repair. > > Incidentally, having two identical monitors is a bad idea. Sympathetic > failure and contagious failure modes has been known to propagate > between the bad monitor and the good. I would keep them apart just to > be safe. > > -- > Jeff Liebermann je...(a)cruzio.com > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558 I'm all for repairing it, but I just want to make sure the repair is cost effective. From the information I've received from this group, and websites, it seems the repair will be very inexpensive if it's just some capacitors. Is there a way I can gain confidence that the problem is w/ the capacitors, before opening it up?
From: saber850 on 3 May 2010 11:20 On May 3, 4:01 am, "N_Cook" <dive...(a)tcp.co.uk> wrote: > Jeff Liebermann <je...(a)cruzio.com> wrote in message > > news:9edst5drns9dhhvmbonl5gds2v615pn9bm(a)4ax.com... > > > > > On Sun, 2 May 2010 17:53:14 -0700 (PDT), saber850 <saber...(a)yahoo.com> > > wrote: > > > >On May 2, 5:10 pm, Jeff Liebermann <je...(a)cruzio.com> wrote: > > > >> This might be of interest: > > >> <http://pavel.kirkovsky.com/2009/03/samsung-syncmaster-204b-repair/> > > >> <http://www.djhome.net/tips/samsungsyncmaster204T.htm> > > >> I've seen both problems on the bench with similar Samsung models. > > > >This is great info; thanks. The website links you found refer to the > > >problem as "flickering". Is that the condition my monitor has, given > > >the video I posted? > > > No, it's not the same. What's probably happening is that as your > > power supply warms up, the cazapitors are starting to also get hot. My > > guess(tm) is that the power supply output voltages drop, causing the > > odd changes to white and black. The symptoms of having the wrong > > power supply voltage vary radically with the type of circuit and which > > capacitors are a problem. I've seen flickering, fades, time delayed > > sudden failure, smoke, fire, and most commonly, just plain no picture. > > Given a specific single component failure, it's possible to predict > > the symptoms. Given multiple partial failures, it's at best a guess. > > > Open up the monitor (it's a royal pain), replace all the big caps > > whether they look bad or not, and live happily ever after. If you're > > into being sure, I suggest you look into purchasing or building an ESR > > (equivalent series resistance) meter, as you're guaranteed to run into > > this problem in other devices that use electrolytics (motherboards, > > TV's, power supplies, monitors, game boxes, router, etc). I use mine > > far too often. > > > <http://www.ludens.cl/Electron/esr/esr.html> > > <http://www.anatekcorp.com/blueesr.htm> > > <http://www.flippers.com/esrktmtr.html> (I have this one) > > <http://www.midwestdevices.com/index.html> > > > More good reading on LCD repair: > > <http://www.ccl-la.com/blog/index.php/category/monitor-repair/> > > Note how just about all the failures are electrolytic capacitors. > > Here's your Syncmaster 204 page: > > <http://www.ccl-la.com/blog/index.php/samsung-214t-repair/> > > Note the they're symptoms include a "dark picture". Hmmmm... > > > -- > > Jeff Liebermann je...(a)cruzio.com > > 150 Felker St #D http://www.LearnByDestroying.com > > Santa Cruz CA 95060http://802.11junk.com > > Skype: JeffLiebermann AE6KS 831-336-2558 > > Could placing a small 12V fan temporarily, at least, in that area be a > diagnostic tool ? Yes, I considered this. Unfortunately, as I described, the problem is very random. For example, it has not surfaced in over a week. So by trying to cool it, I don't know if it's actually helping, or luck. The same problem applies to the suggestions I've received to replace the caps outlined on that website. While I'd be happy to do it, I won't really know if it has helped for a couple months. One thing I'd really like is to find a trigger for this problem. I will try heat today. Is there a way to "stress" the monitor's electronics, to try reproducing the issue? Would changing the image rapidly have any effect? Should I display a solid color (perhaps white) on it? With a reasonably reliable repro procedure (even if it takes hours), I can then get more info, and attempt to fix it, all while having some confidence that my changes have either helped or not.
From: Jeff Liebermann on 3 May 2010 14:23 On Mon, 3 May 2010 04:37:58 -0700, "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote: >> Incidentally, having two identical monitors is a bad idea. >> Sympathetic failure and contagious failure modes has been >> known to propagate between the bad monitor and the good. >> I would keep them apart just to be safe. > >Uva uvam videndo varia fit, right? <http://alkek.library.txstate.edu/swwc/ld/ldex081a1.html> I don't think Samsung uses grape juice in their capacitors. Monitor failures really are contagious. In about 2004, I purchased 9 almost identical Dell systems, all with E173FPF(?) LCD displays. They worked just fine for 3 years, when they started failing. The ones that were the warmest and powered on the longest failed first. Within about 2 months, 6 had developed bad capacitor failure symptoms. What I found amazing was there was one monitor that was left in the box for about 2 years. It was used to replace the first monitor failure, and promptly died about 6 months later. Apparently, they age in the box. When asked by the owner what was happening, I joked that such failures were contagious. Unfortunately, my explanation leaked all over the company with predictable embarrassment. I had to write a company wide memo explaining what was really happening, what I was doing to fix it, and apologize for my bad joke. (However, I didn't promise not to do it again). -- Jeff Liebermann jeffl(a)cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
From: Jeff Liebermann on 3 May 2010 14:33 On Mon, 3 May 2010 08:09:58 -0700 (PDT), saber850 <saber850(a)yahoo.com> wrote: >Is there a way I can gain confidence that the problem is w/ the >capacitors, before opening it up? Drugs work well for improving confidence. I find that I perform my most heroic feats of daring and self-endangerment when thoroughly doped to just below the point of going comatose. This steadies the hand, improves on my diagnostic abilities, and opens me to a variety of unusual approaches. The only problem is that I have difficulties remembering what changes I've made while under the influence and have therefore resorted to using a camcorder or digital camera. This helps answer the inevitable questions "What was I thinking"? I'll refrain from recommending specific controlled substances and prescription drugs as each technician responds differently. For starters, anti-depressants and anti-anxiety drugs work well for elevating one's self-confidence. <http://www.alphacalm.com/anti-anxiety-drugs/> However, if the chemical confidence builder solution is not for you, I suggest you purchase an ESR tester (see previous rant), and test the capacitors in the circuit. Yes, it works without removing the caps. Also, look for bulges, leaks, brown goo, and oozing rubber plugs. -- Jeff Liebermann jeffl(a)cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
From: saber850 on 3 May 2010 23:18
On May 3, 11:20 am, saber850 <saber...(a)yahoo.com> wrote: > On May 3, 4:01 am, "N_Cook" <dive...(a)tcp.co.uk> wrote: > > > > > Jeff Liebermann <je...(a)cruzio.com> wrote in message > > >news:9edst5drns9dhhvmbonl5gds2v615pn9bm(a)4ax.com... > > > > On Sun, 2 May 2010 17:53:14 -0700 (PDT), saber850 <saber...(a)yahoo.com> > > > wrote: > > > > >On May 2, 5:10 pm, Jeff Liebermann <je...(a)cruzio.com> wrote: > > > > >> This might be of interest: > > > >> <http://pavel.kirkovsky.com/2009/03/samsung-syncmaster-204b-repair/> > > > >> <http://www.djhome.net/tips/samsungsyncmaster204T.htm> > > > >> I've seen both problems on the bench with similar Samsung models. > > > > >This is great info; thanks. The website links you found refer to the > > > >problem as "flickering". Is that the condition my monitor has, given > > > >the video I posted? > > > > No, it's not the same. What's probably happening is that as your > > > power supply warms up, the cazapitors are starting to also get hot. My > > > guess(tm) is that the power supply output voltages drop, causing the > > > odd changes to white and black. The symptoms of having the wrong > > > power supply voltage vary radically with the type of circuit and which > > > capacitors are a problem. I've seen flickering, fades, time delayed > > > sudden failure, smoke, fire, and most commonly, just plain no picture.. > > > Given a specific single component failure, it's possible to predict > > > the symptoms. Given multiple partial failures, it's at best a guess. > > > > Open up the monitor (it's a royal pain), replace all the big caps > > > whether they look bad or not, and live happily ever after. If you're > > > into being sure, I suggest you look into purchasing or building an ESR > > > (equivalent series resistance) meter, as you're guaranteed to run into > > > this problem in other devices that use electrolytics (motherboards, > > > TV's, power supplies, monitors, game boxes, router, etc). I use mine > > > far too often. > > > > <http://www.ludens.cl/Electron/esr/esr.html> > > > <http://www.anatekcorp.com/blueesr.htm> > > > <http://www.flippers.com/esrktmtr.html> (I have this one) > > > <http://www.midwestdevices.com/index.html> > > > > More good reading on LCD repair: > > > <http://www.ccl-la.com/blog/index.php/category/monitor-repair/> > > > Note how just about all the failures are electrolytic capacitors. > > > Here's your Syncmaster 204 page: > > > <http://www.ccl-la.com/blog/index.php/samsung-214t-repair/> > > > Note the they're symptoms include a "dark picture". Hmmmm... > > > > -- > > > Jeff Liebermann je...(a)cruzio.com > > > 150 Felker St #D http://www.LearnByDestroying.com > > > Santa Cruz CA 95060http://802.11junk.com > > > Skype: JeffLiebermann AE6KS 831-336-2558 > > > Could placing a small 12V fan temporarily, at least, in that area be a > > diagnostic tool ? > > Yes, I considered this. Unfortunately, as I described, the problem is > very random. For example, it has not surfaced in over a week. So by > trying to cool it, I don't know if it's actually helping, or luck. > The same problem applies to the suggestions I've received to replace > the caps outlined on that website. While I'd be happy to do it, I > won't really know if it has helped for a couple months. > > One thing I'd really like is to find a trigger for this problem. I > will try heat today. Is there a way to "stress" the monitor's > electronics, to try reproducing the issue? Would changing the image > rapidly have any effect? Should I display a solid color (perhaps > white) on it? > > With a reasonably reliable repro procedure (even if it takes hours), I > can then get more info, and attempt to fix it, all while having some > confidence that my changes have either helped or not. So I tried various techniques to try reproducing the problem today, all to no avail. I tried heat. I displayed a solid white image--with the brightness & contrast at their max level--for several hours straight; nothing. I turned it off for ~4 hours, and when I turned it back on, the problem repeated itself. So clearly heat is not a trigger, not is prolonged use. Unfortunately, the "randomness" of the problem persists. Here's more observations: When the monitor is in it's "black" state, it's not as if the monitor was off--there is a very low level of light on the screen, so it's more of a dark gray than black. Is this the backlight? With the monitor in it's "gray/black" state, I pointed a flashlight at the screen at all angles & at a close distance. I do not see any of the image. I noticed that as the problem was occurring, and the screen was fading first to white, and then to gray/black, the image is not being updated. I moved the mouse over to that screen while the fading was occurring, but the mouse on that screen did not move. Does this suggest a defective video board? I also tried adjusting the brightness & contrast, but I couldn't, because the on-screen menu does not show up. |