Friday, February 13. 2009
We live in a world of electronic gizmos, and like all things built by man, they will eventually fail, sometimes sooner that we would like. There comes that time, the moment that you realize that a device you have depended on for years has failed.
The challenge was in simply getting the monitor open. The case is a simple clamshell with a backshell and a bezel that surrounds the screen. This was secured with two screws, found under the desktop stand, and small detent style clips all the way around the outside edge. Separating the clips took a fair amount of force while prying with a slim tool. I did mark up the case a bit, marring the finish in a few places. But as the marks are on the back of the monitor I was not too worried, the priority was on preserving the front and the LCD screen itself.
It was Deb who saw the trouble first. I had just gotten the power supply PCB out and was beginning to examine it. Looking over my should she pointed at some smaller electrolytic caps. Sure enough the tops were bulged outwards in a decidedly unhealthy way, even a little black discharge was present showing signs of complete failure. Removing the capacitors from the PCB and testing with an LCR meter showed zero capacitance, totally dead.
It took about twenty minutes of digging though my spares stock to find the replacements. A pair of 470μF 25V electrolytic capacitors in an only slightly taller case that fit perfectly into the PCB. The new caps were Nichicon PL series, a nice high quality power supply capacitor. No need to order parts from the mainland and wait five days to put the monitor back together. It is going to be a while before my wife makes any disparaging comments about how much of the garage is taken up by shelves and boxes of electronic components.
Solder the old parts out, solder the new caps in, then double check the polarity marked on the PCB. This was made very easy by the single sided PCB construction of the power supply, the old caps just popped out when I melted the pads with the soldering iron, leaving fairly clean holes behind ready for the new parts. I then triple checked the polarity against the photos I had taken before removing the old parts. A bit paranoid, but this comes with lengthy and painful experience. I have gotten in the habit of taking photos whenever I dismantle something, easy to do and being able to check the photos has, more than once, saved the situation when a detail gets missed.
The two capacitors that failed in this monitor were C200 and CE101. There were two other capacitors, of a different value and case size, from the same manufacturer, but I could find no suitable replacements in my spare parts, so they stayed. Hopefully I do not have to open the monitor again in a few months to replace those.
Reassembling the case went far more quickly. Remount the power supply PCB, insert all four screws, replace the EMI cover, and reconnect the various power leads. Simply reversal of the disassembly. What took me twenty minutes of careful prying to get apart went back together in thirty seconds, the case snapped together as it was designed.
The power supply (left) and controller (right) circuit cards in a ViewSonic VA1912wb LCD monitor, the bad caps indicated in red
I have heard it said, that if you want your pipes fixed, don't marry a plumber. To some extent that extends to electrical engineers as well. But sometimes I do get things fixed. Applying power and video the monitor displayed a beautiful, crisp image with no annoying ripples across the screen. This did have one other result, a happy wife, never a bad thing.
This also shows the sense in at least checking failed gear for the problem before chucking it in the dustbin. Who knows, maybe the failure is something simple and easily fixed. If you have the skills it is at least worth trying. This time it saved me a $200 19" LCD monitor.
Update... Fred Obermann had the same issues with an Acer AL2423W monitor. He has posted a series of photos that demonstrate the same process on the Acer monitor, with nice photos of failed CapXon capacitors in that monitor as well.
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Andrew, as someone with a ViewSonic VA 2026w monitor, I read your post with interest. Good for you to avoid the throw-away mentality, and to have the wherewithall to make it work.
Same thing here. Only contribution I can make is my power board has Rev:00A; made by Delta Electronics. The caps are indeed CAPXon but mine are 220uF.
thx for the guide and the inducement to try.
Delta has had some issues across the years. A big recall of Dell laptop power supplies involved a Delta design.
hai, ihave one hp w1907 lcd monitor . it will work few seconds and goes black screen .when the led on. again i off and on the same problem comes how to solve pls help me
Hi all you have to do is to take it apart and replace the swollen or bulged caps.If you are here in us just go to this website lcdalternatives and look up the caps you need or if you open the casing you will find the bad caps. Then go to this website mouser.com and order you caps tell them you want radial caps or the type in which the leads are on the same side. They are very cheap most of them are less than a dollar good luck.
Another grateful ViewSonic VA1912w owner using your fix for a flickering screen. Both C200 and CE101 caps were shaped like Dolly Parton and now replaced so I am flicker free once more. Many thanks.
It appears that ViewSonic sold two models as VA1912w and model number VS10866
(at least in the UK)
One is a VGA connector only model with a DAC-12M030 board and 220uF caps on CE101 and C200.
The other is a DVI plus VGA connectors model with a DAC-19M005 board and 470uF caps on CE101 and C200.
It helps to know which one you have got before you order replacement caps.
I have a Viewsonic VX2235WM with no picture. Is it fair to assume that the source of the problem is capacitors?
Not necessarily true. There are a number of failures that can cause the picture to vanish. The monitor is busted in any case, nothing to lose, always worth a look to see if the repair is easy.
i have the same monitor and it comes on but goes black right after. sometimes i can get it to stay on by turnning it on and off a bunch of times but would like to not have to. any help you have to offer would be great
WHAT THE PROBLEM DELL LCD 17 INCH, IF U ON HAVE DISPLAY, IN FEW SECOND BLACK
But ... how much is your time worth? Was the ROI worth it? Considering the other components are going to fail and new monitors (with new components) are under $150 now?
It sounds like this was a project you enjoyed, so maybe it paid YOU ... but everytime we say "yes" to something you say "no" to something else.
So, did you say "yes" to the right thing?
Probably -- Dave Smith and I enjoyed reading about your experiences, and there were at least three nuggets in there that will use in my tinkering hobby. So there's a trickle down benefit, which would not have happened if you went to Costco that day.
It only took about 1.5 hours to do the deed. $200/1.5=? Not a bad wage for a little work that was fun. Two hundred I didn't need to spend, another piece of electronics not going to a junkyard, at least for a while yet. Add the cost of going to Kona and the time lost buying the replacement.
Though you are right, there is a point when it isn't worth it. But unless you survey the issue, you do not know.
Glad I ran into your post Andrew. I use (2) VA1912wb monitors for graphics and web development. When one of these went out, I was looking at having to replace both since they are no longer available.
Since I'm handy at electronics, the repair cost me $7 in capacitors from digikey and that was for both monitors (just in case).
I did run into a problem with finding caps with the same dimensions and values for the 1000 uF but was able to use the next larger case size.
The part numbers I used were P12383-ND for the 220 uF and P12379-ND for the 1000 uF.
The results were amazing; the monitor that I replaced the caps in looks brand new, sharp and with excellent contrast and colors. The other one I've not touched yet but soon will, is washed out.
Thanks for a great post! Dan
Hi my name is Tony,,,and I want to thank you for your inf about how to repair lcd monitor,,,i read your page ,,and you know what,,i fix this monitor that I found somebody had put it out as garbage,,,its a westinghouse but the parts inside are just like the one you have on your pictures I replace the same 2 caps they where bad,,,you could see no picture when you put it on,,,and now it looks like new
just one problem,,I have like a very fine red line on the right side of the screen from top to bottom is not bad,,,,for been the fist time ever me doing electronics repairs,,,maybe when I was soldering the caps I put too much heat,,,If anybody could give me an idia why this happen is really appreciated ,,thanks again for your inf
The thin red line is caused by damage to the panel not your soldering. If you are lucky try pressing on the bezel just above where the red line starts. If the red line disappears all you need to do is open up the monitor and ensure that pressure is continually applied to that point internally. A piece of folded thick rubber is ideal.
I have a VA912 (about 31/2 yrs old) and the screen takes 30 minutes to produce a picture. I already replaced 6 blown caps, but still the same problem. Should I try other components or give up before I go broke? I tried Viewsonic in Aus. but they want $200 for the card, (I only paid $300 for the monitor, new) If I was to continue, which would I change next?
A slow turn on does not sound like a capacitor, more probably a power supply or a bad semiconductor. Not something that can be trouble shot nearly as easily.
help!! my lcd monitor turns red...but it has a display. the red color appears only in dark backgrounds. when i did not use my pc for 2 days, all things are back to normal but after a couple of days it turns red again..what should i do??...
I have seen something like this before. Sounds like a video card problem to me....
Have you tried swapping your VGA cord with another monitor to see if that's the problem?
My LG 1710 LCD monitor that has a horizontal jagged red line across the lower quarter of the screen. The picture displayed is clear and sharp, however the line appears as soon as power up is initiated with or without computer connection.
Always hard to diagnose from a quick description. But it sounds like a bad line driver or a bad connection to the panel. First guess? Not easy to repair.
Thanks for the quick response. I have downloaded the service manual and have an idea of the line driver you referred to - is that similar to the buffer board drivers in Plasma TVs ( I successfully recovered a plasma tv from the rubbish tip by replacing Y buffer boards).
Read all 39 pages. Very constructive...
My Sum E Vision 17" monitor goes blank just a couple of seconds after start up. Tried it on other PC's and it does the same thing. I checked out other monitors on my PC and there is no problem so that eliminates a motherboard source. A common denominator problem appears to be two faulty capacitors? Absolutely no sign of bulging on the caps or black discharge. Like you I am against scrapping a little used nice piece of kit. I could post a photo of the circuit board... Maybe I am looking in the wrong place.
No problem accessing the works.
I'm not a techy whizz so any advice appreciated here in Edinburgh.
I'm stumped on my 24" acer LCD.. It just went black on me one day in the middle movie on my PC. I got a new monitor 3 days later and put the old one in the corner for about 2 months. So I was just curious last week and decided to see what I can do to fix it. I saw a you tube video on how to fix busted capacitors on an LCD monitor ( seems to be the problem most the time) So I opened it up, marked all the cables and took a look at both the boards ( assuming 1 was the video board and the other the power supply ) I noticed 5 capacitors were kinda puffy/rounded on the top ( Far as what I saw on many videos and pictures on bad capacitors these were bad capacitors) I ordered the capacitors I needed and got them today. Replaced all the bad ones and put everything back together ( double checked all the connections and made sure it was all back the way it was) I left the back off just to test it first, still has a black screen . Checked all my connections again and there good to go. The monitor will turn on and the light turns green like its receiving a signal. Its like the screen is getting no power. After I put the original monitor back even the resolution is set to the old monitor. So my Question would be is it a bad video board? and would it be worth repairing?
signal failure with my hp monitor if i connect VGA cable into the system unit then it come on and off
Thank You Andrew! The monitor has not been so clear and bright in a long time! Your wife is so very happy that you had time, parts and know-how to fix it so quickly
It would not have been acceptable to her to have to replace it with a new, substandard monitor that was not its equal nor to have thrown this one in the recycling. Not to mention making her happier much more quickly than she thought possible AND having saved soooo much $$$$
Thanks a lot for the opening instructions!
Saved me a lot of time!
I have the same model. Guess which were the faulty caps? C200 and CE101...
Thanks a lot,
I have an Acer X2 LCD im working on. It's original problem was that it displayed a "wave" of red "lines" (horizontal or vertical, not sure). I replaced the video board and it fixed the issue, but now it only comes on for a few seconds then shuts off. Any ideas beyond this?
Yep. I bet it's the PSU. I'm not sure but I bet this has the same Integrated PSU as a couple of KDS brand monitors that I fixed a few months back. During my research of the problem I found that this PSU is used in many LCD monitor brands, including MAG & Acer.
It was as simple as replacing 6 470μF caps and one 220μF and poof, no more problem. You know how to solder, right?
This is a reference page that I used for info on the PSU in question:
Good job there, Andrew!
I had a similar situation with a Dell 1702FP: two tiny bad capacitors. I fixed it and then created an instructable to tell others (like your website). I received many success emails and lots of comments. It feels great, I mean, tons of monitors were saved with one instructable. I suggest you too post an instructable with clear keywords, and you will help many more people and save our landfills from hazardous materials.
Here is my instructable (or click homepage next to my name):
This is nice. I actually am working on a friend's Chimei CMV221D right now, and as some may know, Viewsonic and Chimei monitors are basicly identical twins. The problem with my friend's 22 incher is the backlight, it won't turn on at all. Initially, it would turn on, and then off after 5-10 seconds. After taking the monitor apart in the exactly the same fashion as you, I was treated to a sight almost the same as you as well. Except I am not confident enough in my skills to identify which caps are dead/dying or not (to my eyes, pretty much all the black caps looked like they were bulging to a degree, some with the black discharge), I decided to simply buy some "neon light" style CCFL inverters instead. Waiting for them to come in the mail now. =]
I would advise against using the CLF lights to replace the backlight unless you can guarantee that they are rated the same as the light that is in there, and that's not really likely.
If it is more, they won't work, if they are rated less they could pop the first time you turn it on.
Another thing that is more likely is that the power supply that feeds the light is bad. If you trust your soldering skills then just replace all of the caps that look like they are bulging. If you go to a good parts supplier each cap would likely cost less than $1 for a typical 470μF. While someplace like RatShack (not recommended) they could cost about $3-$4 each.
As always when working with electronics, be carefull. Even a low producing cap can give you quite a jolt if you aren't cautious.
Andrew, how did you determine the caps were bad?
Thanks in advance!
"...[they] were bulged outwards in a decidedly unhealthy way, even a little black discharge was present showing signs of complete failure."
Bad caps will have a raised top. You can feel for them with your fingers.
This problem plagued Dell systems where I replaced dozens of
system boards that had bad caps.
I got to a point where I could tell by feeling the caps alone.
By the way, I have a CTR Hyundai HCM-421E that i'm repairing now. It's original problem was sometimes the screen get greenish and after a hand nock it returns normal. Any hints about this? or have someone the circuit diagram?
Sounds like something with the video input. I'm guessing it uses VGA? Seems to me like some of the colours are going out of whack.
I've found if things get better with a tap that the cause is shoddy solder connections
CapXon or bad name caps i replaced the caps in my tv with Panasonic (FC Series)
thay have a lifetime of 5000 hours and a max temperature of 105°C. instead of haveing 1000 hours of life and a max temperature of 85°C like the CapXon have
i get my caps from digikey.com
nice fix Andrew.
The cap I used were 105C long life caps, for small volumes the cost difference between cheap and good caps is usually negligible.
I know Digikey all too well, waiting for another order right now! There are no decent parts stores on the island, everything is ordered from the mainland.
Thanks for posting this article! I have a OptiQuest 22" (1 year warranty, expired) that just went out on me. After reading this, I had the courage to open things up, get into the power supply module, and voila: I have Four electrolytics with bulged tops, none of them leaked their electrolyte however. A few are the CapXion brand. I might have some caps in my parts piles, but they would be old, so I plan to get fresh ones at RadioShack and we'll see if I can resurrect my monitor.
Don't get the stuff at Radio Shack, probably as cheap as the originals. Order it from a supplier like DigiKey (www.digikey.com), you can get exactly the right one and it will be from a reputable capacitor manufacturer.
You need the capacitiance rating, voltage rating and the case size (diameter, height and lead spacing in mm) from the old caps. It will take some looking but you will find one that fits. Spend a dollar more and get high temperature, long life caps rated at 105C.
I appreciate the beautiful heart you have but how I can go abt a compaq lcd that has power led on but no display. thanks
I have a Viewsonic VA1912wb. There were lines running top to bottom and red lines.
I followed your instruction and found 4 caps 220uf(2) and 1000uf(2).
I replaced them all and now the monitor works great.
I've got a similar monitor that was being pitched from my place of work. I found bad caps and replaced them as well. The monitor still does not work very well at all, with an unusual and occasional arcing noise being heard from inside the case. This one would be too expensive and labor-intensive to repair, so I fear this one's headed for the recycling center. Got any ideas what might be causing an arcing noise? HV to drive the lamps?
Andrew - Thank you so much for taking the time to detail your experience. I was about ready to chunk this monitor. The C200 and CE101 are bad on mine as well as a couple of the larger ones (they actually have black oozing out the top). I have a friend who said he would solder mine for me but I want to take him all the stuff. My question is that the cap you show in your picture says 220μF 25v on it but you say you replaced it with a 470μF 25v. I know nothing about caps, so do I just go off what the old CapXon caps say or something else?
I have a Westinghouse model LCM-17v8, The picture of the powersupply and motherboard appear identical, except the caps in question are 220uf 25v, I was wondering if the difference is because of the 2 inch difference in the screen, and that maybe I should get 470uf instead of the 220uf's.
Do you have any input on this, I can email you a pic of the boards if you want.
Thanks a bunch,
This article set me in the right direction on a Viewsonic VX2235wm. I replaced the 2 caps as you had, (they were 220uf caps) and also 2-1000uf caps that were manufactured by 'CapXon'. The monitor went from no backlight to a working unit,
Thanks again, Mike
I have a Fujitsu Siemens 19'' SCALEOVIEW C19-1A LCD that has the same backlight issue. I opened the case but could not determine which of the caps are bad. they all look healthy to me. I check closely but could not see ant leakage. There are 4 PCB's and I do not know which of them holds the backlight. There is this particular one that had a few wores going into the LCD case and it has two 25v 150uF cap and I suspect the two(C201 & C223) are the backlight caps. Have you perhaps ever worked on monito like this? I cannot afford to buy a new one but I might find caps of the same rating in the lab.
Has any one attempted to repair a Gateway FPD 1960 H LCD?
I have one that I have not been able to find a replacement inverter for.
It would be great if I could find enough info on how to repair it or find a substitute inverter for it.
Any help wpuld be welcomed please reply "fixing gateway"
Cheers to all.
Thanks Andrew! I have a Westinghouse LCM-19w4 that had the exact same problem. After opening it up I discovered the exact same 2 caps where blown. My monitor was a little tricky to put back together...the ribbon cable connecting the buttons to the control board is very short.
Thank you for saving me $200!
Mine is doing the same thing. I think I'm gonna crack it open tonight ot check but I need to find my soldering gear before I fix it (I don't need a 5th soldering pencil).
Thank you for the pointer. My wife's Viewsonic va1912wb was experiencing the same problem with the exception that there is no backlight at all until the unit warms up.
I was planning on cracking it open and taking a look- I would have caught the caps at a glance- but you saved me time because I'm getting the parts ordered tomorrow without the disassembly.
Gotta find my solder station and grounding kit!
hello andrew thank you so much for this useful guide, It worked like a charm! I took the liberty of posting the procedure in my forum community
(in spanish) I hope you dont mind, I am sure It will help a lot more people!
Thank you andrew. This information help me a lots, now i don't have to be afraid if my lcd has failed.
very nice write up how to fix monitors.
I have fixed a fer viewsonics in the past with the same issue.
But the one I got now is the mystery. It is VX2235WM and it had the back light problem, so I replaced a few caps and now back light works fine. But monitor is very blurry and colors are faded, I do not know how to explain but there are 2 pictures of the monitor:
But the on screen menu is nice and colorful and sharp in detail.
Any idea what could be the problem ???
Thanks in advance
Great repair instructions! I took home from work a broken Dell 1905FP that wouldn't power on. I replaced 2 of the distended blown capacitors 100uf10v with 100uf50v from radio shack. and now I have a great 19" free monitor. Cisco ccna exam
simulator with FREE CCNA Certification lab.
How do you get the case / shell of the Dell 1905fp apart?
I also have one that won't power on.
Got any other suggestion for me with repairing this model monitor?
Getting the case on a modern monitor apart can be tough. They are not meant to be repaired and do not assemble with screws. Generally there are a series of plastic latches along the edge of the case that must be pried apart. Do not expect to do this without marring the plastic a few times. Just go slow and try different directions.
I have same power supply problem with my LCD 1905FP. the description of the problem is that when it turns on after 5 minutes, the colors are mixed up & the screen got devided into two halfs .
the condition of all capcitors is visibllay ok (not expanded or leakage etc)
Please guide me in fixing the said problem.
waiting for your kind guidance.
From the non-technically trained folks I give hearty thanks! ...and a suggestion for the instructions.
This may be obvious to someone who's done this before, but it took us a while to figure out you can unscrew the tan board, and detach the one plug that attaches it to the green board...which allows you to actually get to the solder points
Also, it turns out I didn't have the solder I thought I had, but there was enough on the contacts to attach the new caps
For us it was the main caps that were blown, but I picked up a set of the backlight ones too - figure it's better to have them around! Thanks to #2.1.1 Dan for supplying the digikey part numbers, worked like a charm!
I have a Samsug 172n lcd monitor that would power off after a few minutes of usage. I replaced a capacitor and powered on the unit without putting on the casing. Well, the PSB mustve touched the metal part of the LCD panel or something because it generated a spark and a puff of smoke. Do you think my whole PCB board is damaged or could it be a blown fuse or something minor? I'd like to keep the monitor but Im not shelling money for a repair when I can get a new, bigger monitor for about 100 bucks.
I repaired an LCD monitor that had a short as the AC in jack. When I reassembled and turned it on, the image is off center by about 1". The various menu controls do not touch this off center problem as it appears the the area capable of supporting an image is off center. Could this be a pressure problem or some sort of incorrect reassembly? I did tear up the foil tape on the for edges of the component board a bit. How can I readjust this?
Unfortunately the answer to that one is probably out of reach without detailed knowledge of the specific monitor. At best you can recheck the assembly for any problems.
Andrew and those who left comments,
I can't thank you all enough for the information that this web site has provided. As a fellow EE, Andrew, I read all of your descriptions with a smile. My mother and wife could never figure out why, after all those years in college and graduate school, that I still could not fix her television set when it went on the fritz. She just would NOT accept the theory that as an engineer my time was just too valuable to waste troubleshooting the problem. My time would be better served PAYING for the technician to come out and fix the problem. It would have done no good at all to explain that my specialty was digital electronics and simulation either. I don't think I was a failure in her eyes, but the diploma on the wall in her bedroom (she wanted the MSEE diploma) probably didn't get dusted as often as it used to.
I replaced the same two caps that you did Andrew. And like someone here noted, they WERE 220 uf and not 470 uf. I was amazed how well anotated the circuit board was. It would have been very difficult to install the cap with the wrong polarity. I didn't have a great problem getting into the case, but it WAS the toughest part of the job. I actually had to get in TWICE since I somehow forgot to reinsert the backlight connectors when putting everything back together. The totally dark screen on powerup reminded me what was wrong. In my case all the other caps looked in very good condition. I don't have a large collection of spare parts in the garage (only Ham Radio and Computer gear there), so I had to go to Rat Shack to get replacements. Luckily they still carry some components. Total cost 2X$1.39 + FL Tax. (I'm retired so I won't count my time).
Thanks again to Andrew,
JR in Parrish, FL(near St. Pete/Sarasota)
73 - WJ3R
Sir, I have a problem with my LCD veiwsonic VA1918WM widescreen first it doesnot display if you open any black screen game loadind , movie etc but afterthat it turned off parmently i opened it so one transistor (P2504BDG) was burned then i put new transistor (P60NF06) then Lcd on for 2 min and its burning again why. \should i put the same transistor remember there was two transistor of same number which give disply.
Ran into this page by accident, was actually looking for a new power board. Anyway, followed your advice fortunately I have some electrical skills. Only replaced the capacitor by the fuse and it fixed my problem. Monitor is a ViewSonic VX2235wm.
Hey I have a Viewsonic VA1912w, the board layout is very much similar to this one. The problem being I believe the back light doesn't work. The monitor shows a green light and shining a light source onto the screen shows a picture.
When opening it I found the same two capacitors that you have removed to be blown as well, however after replacing the monitor's light still does not turn on.
Do you think it may be the backlight itself has burned out? The monitor is only about a year old.
The back light is definitely out, but I would guess the power supply is out, not the EL back light itself. This supply creates the high voltage used to light the electroluminescent sheet. The caps I found blown were in the EL supply.
Great post. I'm working on a co-worker's Viewsonic VX2433WM LCD. This display was not powering up. The screen would brighten up for a second but then go dark. When I hooked up to my PC as a dual display my computer recognized it but that's it. Once I got to the Power Supply board the first thing I noticed was two browned areas near the two small IC (guessing they're for the CCFLs). Then after reading your post I checked the Capacitors. Yup, most of the Capxon caps look just like yours.
Two of the caps you highlighted in red are the same ones that I found to be going out as well. Here's what I have in mind to replace:
C200 200uf 25V
CE103 1000uf 25V
CE101 220uf 25V
CE109 220uf 25V
CE102 1000uf 25V
I can usually find the 200uf 25V & 1000uf 25V caps on the same site but the 220uf 25V shows up on some other site. I'm headed up to Akihabra in Tokyo to shop for parts. If replacing those doesn't bring it back online, what do you recommend after that? Worst case I can buy a new PS online for $50 but I'd rather beat this thing at its own game first.
UPDATE: It's alive! The trip to Akihabara was a success. The vendor pointed out that 200uf caps I thought I needed was in fact another 220uf. The man knows his parts. The actual removal & installation didn't take long. Reassembly was relatively quick. Once the unit was reassembled it powered up and looked great.
Now I'll be on the lookout for stray LCDs sitting in junk piles. Thanks to everyone for the great info posted here. It was very satisfying to actual bring something back from the dead.
Congrats!! It is always satisfying to fix something like this.
At the waste transfer station there is a spot in the corner where everyone piles dead appliances. I find myself looking for LCD monitors now, knowing I may be able to fix simple failures.
Thanks for the great article! I'm trying for my third functional monitor from the throw-away pile; my first one just had a blown fuse and was easy to fix, the second one would not light the CCFL lamps so I stripped out the panel and mounted it to an overhead projector. It's great for movies, but a little bulky... I'm off to buy some caps now, (for a NEC LCD1970GX that has a very similar inverter circuit - on the main PSU board, with two caps at the head-end) hoping to increase my stats from 50/50 to 66%.
Thanks again. Great info!!
I've got the same monitor, but my monitor won't do a thing. So I pulled out the power supply board and all my caps LOOK good--they're not bulging or leaking, no burn marks on the board anywhere. The caps are a mix of CapXon and Taicon. Should I just replace all of the caps or is there a way to troubleshoot this thing that an amateur can figure out?
If it is the caps and the power supply you can check the power supply output voltages. Make sure you have some reasonable voltages on the connectors that leave the power supply. If not that, it is likely beyond a simple fix.
Thanks for the post Andrew - it helped me save my Viewsonic (a VA902b)!
It is out of warranty, but when I saw your post before throwing it out I decided to open it up and poke around.
Sure enough there was one bad looking (bulging) cap ... 1000 uf 25V.
I found in my supplies a couple 500uF 20V caps that I put in parallel and installed in place of the bad cap.
Although my caps were much bigger, I had room to lie them down in the available space.
And even though my caps were probably 15 years old (!!) they did the trick and my monitor is alive and well again!
Thanks for the guide Andrew. I would never have tackled a repair without it. Now, having replaced seven bulging capacitors, I have a working VA912 which was previously earmarked for the dump. Cost of parts - £5.04
Thanks for the info.
Now that you've completed the repair, if you were to open the case again, would you do it differently? In other words, is now is there a better approach to opening the case without marring the surface now that you know exactly how it's put together?
Not sure if it would be possible. The case was not designed for maintenance, but was clearly intended for a one time assembly before shipping. Even with knowledge of how the closures work I do not see how to get past them without some prying and marring the case.
I guess I was wondering that if you happen to know where the catches are and if you were to slide a slim tool in there, you might be able to pop them one by one rather than randomly torqueing the case. Does that make sense or it is hopeless?
Thanks -- Greg
You may be able to minimize the marks through more patience than I had, but I suspect a few mars are inevitable.
Now that I've completed my repair, I'm now able to answer my own question. Instead of a screwdriver, I used some useless credit cards to get the case open. The thinner the card, the better (American Express sent me some bogus cards that were pretty thin so I used those). I took one of the cards and sanded one edge to a taper by rubbing it against some sandpaper laid flat on my workbench. This made a nice thin edge which allowed me to slide it into the case seam. Apply some force to get the card in and try to put pressure on the back side of the case inward (away from the seam) as you go. Keep working the card around the case, you may need to pull it back out and push it back in at some points. Each time you open a catch, you will hear a popping sound. I though I might be breaking something, but I wasn't. Once I made a large enough crack, I then slid more cards in to keep the case wedged apart and from closing back up. A little patience, and in a few minutes I had the case completely open with no damage at all to the plastic.
To those who question the value of this repair, I think it is definitely worth it. It's cost effective (cost me $1.60 and some gas to get to the surplus store), eco friendly, and satisfying. Shame on Viewsonic for using such low quality caps. Not only does that do a disservice to their customers, but also to the environment. The VA1912 is a good monitor otherwise.
And thanks again Andrew for sharing this experience. This page was exactly what I was looking for and it gave me the confidence to do it. I hope people continue to rescue these and other displays rather than pitching them.
I have a va912 that doesnt work at all. led indicator does not light up when plugged in , is this a case of the fuse needing to be replaced? I am a amateur at repairing electronics but i know how to use a soldering iron, is this something that i can fix ?, if so where do i look to to get a replacement fuse? I see the one on the board and it says says replace with an F101.
Impossible to diagnose over the internet. At a minimum, open it up and look for any obvious issues (like those described in my posting) before you chuck it. You may get lucky.
You can check the fuse by simply changing it, or checking it with a multimeter.
Thanks andrew, upon examination i found that 3 capacitors were bulging , one with dark residue on it.
Hey, I just wanted to thank you...
I've had that same issue with my screen (same model, VA1912wb) for quite a long time and I couldn't figure out what the hell was wrong... every Google search pointed to lower the refresh rate, but I knew that wasn't the problem.
I live in Argentina, and here it's not so easy to own an LCD monitor (although they are becoming sort of a standard slowly), so the idea of replacing mine was out of the question... and even sending it to repair was sort of an issue, 'cause everybody tries to rip you off (yeah, we're THAT bad).
So, kept on searching 'til I found something that would point me to an answer...
On one single page, someone said it could be a capacitor problem, and since I have absolutely no knowledge of electricity, I read a little about that, trying to learn what it was... well, it made sense, so my search was now pointing towards the capacitors. That's when I found this website.
Your explanations, and precise instructions were so helpful that a guy like me, with no electricity knowledge whatsoever and a pulse that couldn't safely handle a solder, manage to repair the monitor!
Now it works absolutely great, there are no lines, not a single one! And all it costed me was $0,60 for the replacement capacitors (and I'm talking Argentinian Pesos here, that's about 15 cents in US dollars!).
So, again, to sum up this long long post, all I have to say is: THANK YOU!
Andrew, awesome post this is really great information. I was wondering if you might have any idea about what might be wrong with my 20inch dell monitor. The problem is that is does not power on at all, when I opened it up and gave it thorough look all the caps look intact not bulge on any no discharge. My question is what next do you think that this might be a backlight issue? how can I narrow down the problem.. Thanks
Anyone else have an idea please let me know!
hi, my screen hasnt been turning on either, came back to my computer and the screen is complatly dead, little standby light wont even turn on.
Iv opened up the circut board and have been checking the caps with a muiltimeter. None of the caps are bulging, but the resistance levels i been getting have been a little strange, but this being the first time iv ever checked caps, im not sure what they shuld be.
I think ill end up replacing them first, but just to check, what resistances should i be getting from the caps?? and if none of them are "dead" dose the problem lie elsewhere?
330uf 25v cap is reading : 18ohms, is that low and needs to be replaced? What should it read?
If you want results for all of the caps I can provide them.
Measuring the resistance of anything in circuit is difficult, it depends on what other components are connected. Out of circuit capacitors should read a very high value as they are essentially an open circuit.
Another thank you!
My VA1912wb flaked out months ago. At first it would work after 'warming up' for a few minutes, but soon it wouldn't display at all. I set it aside and bought a new one. Recently, I needed a spare monitor and didn't want to buy a new one, so I took another look. Google quickly led me to your site.
I took it apart, following your instructions, and found four bulging caps. Even though I've never soldered before, I decided to give it a shot. A few bucks and a little careful soldering later, it works again!
I just have to love these sort of comments!
Congratulations on the repair!
Found your page while looking for a reason why my monitor was flickering. Took your advice and bought some caps. I live in Central Oregon and no one here had any. China's new year or something. Found a place in Cal. ( All Electronics Corp., 14928 Oxnard St., Van Nuys, CA 91411-2610, FAX: 818-781-2653 ). Looked up Diga key and wouldn't have them til March. I don't know how long they will last but they do work. $8.60 total. I have my monitor back working like it used too. Thank You so much for your detailed info.
All Electronics is a good outfit. I have ordered stuff from them many times over the years, never a problem.
Hi, Andrew, I have to say I'm really pleased to see a kind hearted soul on the old internet, sharing knowledge and saving so many monitors from the scrap heap. Not to mention the joy that many people have experienced as a result of following your advice. Well done sir! Now, if I may? I'd like to request some advice regarding a monitor I've had kicking around on the floor for many months, largely because I couldn't bring myself to throw it away. It is a HP w20 lcd monitor which will sometimes come on and work perfectly for an hour or two, and then gives a message of 'no signal detected', and then goes to stand-by. At other times the display will come on for only a few seconds then go back to stand-by again. At other times, the display will come on, but fairly dim and a little blurred, slowly coming to full brightness and clarity, then maybe it will stay on for a while, or it might just go straight back off to stand-by again lol. it is almost like i have to tease it into action sometimes, I can turn it off and back on and it might work for a few more seconds then go back to stand-by, or occasionally it pops right back and works properly for an undisclosed period. It is defiinitely not a pc or lead related problem, I did all those diagnostics first of all, many moons ago. So having said all that, the first time I took it apart I found a very bad solder joint (big empty hole with a smidging of solder at one edge) on the 240v input (that would account for the high pitched squealing/crackling I used to hear sometimes, right?). Anyway, sorted that out, reassembled the monitor and it worked perfectly, for a few hours and then back to old tricks again. So today, having read all the positive comments on your site, I decided to take it apart once again, but unfortunately all the capacitors on the power and the video board look perfectly formed and no leakage. I have the power board out on the bench (I'm assuming it is a power fault) and all the tools necessary for any surgery Do you have you any ideas/suggestions for me please Andrew? I've done plently of soldering and swapping visibly busted components in my life, but never had the knowledge of how to approach these more complex matters. However, very willing to listen, learn and spend a few dollars on parts if necessary. Any advice would be greatly appreciated.
Hello again, just to follow up my last post, I took the time between my post and your reply to educate myself about power supplies, and how ac voltage gets converted to dc voltage using a rectifier. I then found out how capacitors are used to smooth the dc voltage, before been regulated (if necessary for the application) to create a cleaner more stable dc voltage. Oh, I also looked into step-up and step-down tranformers, as they were clearly visible on my power board too. All interesting stuff I'm really glad I came accross your web page, I've become totally inspired to learn more and more. Anyway, having absorbed this new information, I've been looking around the power board and identifying which component does what (and looking up the data sheets for each component so I know exactly what I was looking at), and then attempting to trace the path of the electrical flow on the circuit board in a logical manner based on that information. It all seems pretty straight forward, but very complicated at the same time lol. Nevertheless, I was just wondering, based on my previous description of the monitor fault I'm experiencing, and my newly found knowledge, could this component TOP247YN (integrated off-line switcher) be to blame? The reason I am isolating this particular component is because of its function (i.e., it appears to be the only component that actually switches the dc output on and off remotely. among other things) and I figured that if the component were breaking down, perhaps due to overheating (which would fit in with the intermittent nature of the fault), that might produce the problem I'm experiencing. Just a thought. I bet I'm getting well ahead of myself here, and that it has no relationship to anything relevant lol 'a litttle knowledge is a dangerous thing'. I look forward to your reply. Regards, Warren
You describe erratic operation with little common denominator. The rule in these cases is to look to the power supply first. Low or noisy voltage in the power supply will cause unusual and erratic behavior. Start with the electrolytic capacitors, these are the most likely parts to fail in a power supply. Caps can also fail gradually, leading to marginal operation.
The switching controller you have identified is a member of the TopSwitch family of parts. These are designed to do AC/DC switchers and are common in small power supplies. These usually fail completely, partial operation is uncommon but I suppose possible (never seen it). These are often used for the standby part of the supply, providing power to the circuit that controls power to everything else, including the on/off button.
Hi, Andrew, thank you for the prompt response. Fingers crossed, I think I've solved the problem (It's been working for about 8 hours now and is bright and clear with no signs of failing). It turned out to be more bad solder joints. I re-soldered around the following components: the toroidal coils, the rectifiers, all the capacitors, and the transformers (basically everything with a leg, but not the surface mounted stuff). Anyway, that appears to have cured it YEEHA! Which, I might add, fits in nicely with your assessment and diagnosis of low or noisy voltage on the power side of things, does it not? I hope this lengthy tale might help someone else to solve their problem one day, and as for me, for future reference I will adopt your rule of thumb regarding 'erratic operation with little common denominator'. Without your web page and the positive nature of the comments and replies I saw, I would never have set about this task with as much vigour and determination as I did. Thanks a lot, and keep up the good work Oh and if anyone else is interested, here is the site I used to teach myself a little bit about electronics, it was really helpful: http://www.kpsec.freeuk.com/study.htm
I have an Acer AL2423W monitor and 6 months after the warranty expired, the monitor also expired. When I contacted Acer for information about out-of warranty service, they sent me an email explaining that if I would send them $60.00, they would be happy to talk to me on the phone for up to 30 minutes. Evidently Acer has no interest in fixing their old stuff; they want to sell you new stuff.
So, inspired by your post, I took the thing apart and replaced all of the failed capacitors, put it back together, and for less than $15 I have a working 24" monitor again. Who knew that working on my dad's Heathkit projects back in the '60s would pay off 40 years down the road?
There is a page of photos that document the process at: http://sundancer.us/misc/al2423w/index.html
Thanks Fred! That helped a lot! I have a Acer AL2423W as well. One thing that I might add (again thanks to your detailed photos!), I was able to take the back clam shell off pretty easily with two flat-head screwdrivers. Working instead from the bottom center out toward the sides. Placing a flat head screw driver in the catch and pry it 'up' towards the back of the monitor seems to pop the 'latch'. Then leap-frogging with the second flat head screwdriver at the next catch. Working half way to one side and then the other. And eventually the top. The cover came off in about two minutes. I hope this will help the others. Also ordered my capacitors off off Newark.com.
Thanks again everyone! You guys just saved me $200+!
I had the same problem with my Acer AL2423W.
It's gone after 6 months and had been in my closet for 2 years.
Finding your web page, I replaced 4 capacitors to new one made by Sanyo WG.
I only invested 10 dollars for the capacitors and iron.
It works well now! Thanks a lot!
I have a westinghouse 19" LCD that has a very similar power board, replaced 2 220uf 25v caps and still have no backlight. This was a work computer and our video cameras show that the screen just flashed white then stopped working. Seems weird that it had bad caps and that wasn't the problem, im pretty sure its not my solder points but im going to take them out and resolder them for fun.
Great walkthrough Andrew. I have a Viewsonic VX922 that cost me a pretty penny back in '07 and stopped working last year (backlight flicker and then black image), I'll go through my spare components or go shopping for new caps and fix it up. My power supply has CapXon caps too, 6 of them are bulging though none are leaking (yet):
3 x 470uF/25V
2 x 1000uF/10V
1 x 470uF/10V
I'll post a comment with any info once I'm done with the repair.
Well, I had to visit three electronics shops here in Tijuana to find all the replacement caps, but the monitor is working perfectly again.
I was going to post pictures of the repair but they would have been mostly the same as the ones in the post except with more caps marked in red!
Thanks again for this post Andrew.
Not having an Acer monitor around, I have no idea. Modern monitors usually snap together with small latches molded into the plastic. They are not intended to be dis-assembled.
Getting them apart is sometimes fairly difficult. You have to pry the shell apart. Marred plastic and broken latches are the normal result.
Please see post #126.96.36.199.1 above. It's in regards to a Viewsonic, but it may also apply to your Acer.
I recently picked up a Viewsonic VG2021m from the curb. I got the same results with both the VGA and DVI cables on two different PC's. Upon startup the LED would change from orange to blue, screen stayed black with only two flickers of light about 30 seconds after LED changed to blue. I read this entire page then opened the case and removed the cover from the boards. Sure enough two capacitors had bulged. I replaced both, but it did not effect the screen. Same results upon startup with two different cables and PC's. What next? I can take care of the soldering but finding the problem parts is not my forte'.
Can you offer any suggestions.
I also have a Viewsonic VG 2021m that has the same problem, After blue power light comes on the screen may light for half a second and then it goes dark. There is a momentary hissing sound. Shining a bright light at the screen shows that the picture is still there, just no backlight. I suspect that the bad caps are to blame but I would suggest replacing all of them, since you may not be able to spot a bad one,
I have the exact same problem on a Viewsonic VA1912WB. It looks like the backlight is trying to lit with no success. In my case, the hissing sound is accompanied by a flash of light with horizontal lines on the screen. Just after the flash, I can see the image from the computer appear for half a second then disappear. It does that about 5 times, when the resolution changes, it seems, then stops. The temporary solution I used is to POWER-OFF / POWER-ON the monitor to provoque a new trial of backlight liting. It works with patience after more then 10 times this sequence. So I did open the case to find which capacitor was bad, and verified every one of them and they were all up to their value. So at that time I tought that the problem was elsewhere...
Can you tell me if you corrected your problem by changing the capacitors on your monitor ???
I would like to ask help about my samsung lcd monitor, the problem is that no display to come out. but power led is light. what would be the problem? can u help solve this problem.
wooooow . I just read this whole entire post. Gives me hope that ill be able to fix my monitor. I have a Westinghouse L2410nm, regret buying this monitor now after all the dirt i found out about it. Whats plaguing my monitor is that I have to keep my brightness very low. If I put it high, the screen starts to flicker and eventually goes out. Makes a nasty buzzing noise before it goes out. I suspect I have bad caps so im definitely gonna check that out. I always suspected that but after reading this im sure im gonna find a few bad caps now. What do you think? could the flickering be the result of a bad cap? thanks in advance sir
Thanks for your effort... Been suffering a long while with same issue.... vx922 Gonna repair that shit sceen. THANKYUOOOOOOOOOOOOOOOOOOO dUDE...
Hey guys. I've fixed a couple of monitors I've purchased off of eBay by replacing their bad caps. However this most recent monitor has given me quite the headache. It's a 22" LG Flatron L227WTG. I have replaced all of the electrolytic caps and the initial problem still remains. When plugged in (vga or dvi) the screen has beautiful colors, but it flickers, constant static that is almost brain scrambling. The image is their just fine but I can't seem to locate the problem of the static, or whatever it actually is. If anyone has any insight or has had a relevant problem I would be extremely appretiative. Thanks!
Thanks for the great info. I'm I have a wiesonic se710 monitor that is very dark on the left side of the screen. I can see the picture but its real dark. The right side of the screen is fine. Contras and brightness bothe seem to respond properly. I haven't even opened it yet but I'm guessing the backlight is either not fully powered or or just half broken (is that even possible?) Any suggestions on what to look for?
I have an Acer X193W with a screen that goes black after just a couple of seconds. The stupid thing crapped out after just a few months' use. Anyway, I'm pretty sure I can fix it...except I can't figure out how to get it apart!
The case doesn't match the AL2423W that Andrew posted the great photos of. I see the screw which is probably holding the back on, but it's not accessible because the stand is in the way. And I can't figure out how to remove the stand's two screws because the back of the screen is in the way. (I wish it had the four nice little screws on the plate mounted to the back, but clearly Acer changed the design because they don't want us to fix their junk when it breaks!)
Can anybody tell me how to get this beast apart?
Thanks for the "how-to" guide. I have a strange problem, and I don't think it's the capacitors, it's a Scaleoview c19-11, and the PCB's are almost identical to the one's that you have posted.
Issue: From coldstart it can take up to 20 minutes before a picture is showed on the screen, if not the screen turns on and off with a 2 sec. delay between on and off. When the screen finally appears - then everything works just fine.
Solution? I have already taken my screen apart, but could not find the "error". This started to happen last year around December..
Here's some strange behavior of the HP tft 2025 monitor. Actual picture is too bright ! So there's a too much brightness now, black screen is actually gray and you have to lower contrast to 20 % to have at least some picture ) Any idea?
I have been searching the internet unsuccessfully looking for assistance with a faulty monitor. I found this link and decided to ask for your help.
My monitor is a Dell 1907FPc 19 inch LCD purchased in 2006.
The problem happened app. 2 months ago. The screen suddenly went WHITE, bright brilliant white with the power light still on. No lines , blotches
or other anomalies were present.
I know it's not my GPU since I have this borrowed monitor hooked up and working.
After pricing new monitors since then I decided to attempt to repair it myself so I disassembled it two days ago but found no bulging capacitors. No leaking, bulging or corrosion on any of them. Although I can't be certain of their condition without electronic testing they at least appear to not be blown. So what else would cause this? I've read that a blown backlight would cause a black screen but could it also cause a white screen?
Can someone possibly post a test procedure for the main components?
Since a new monitor isn't in my minuscule budget any help would be greatly appreciated.
Capacitors are the easy problem to fix. Beyond the caps it gets difficult. Without schematics and detailed information on the circuit it probably is not worth trying.
An all white screen may indicate the drivers or the main decoder IC. Not something easily troubleshot.
You are the man. How simple. $8 for 5 caps (that included shipping and handling) for a $200 monitor! Thanks. Great there are people like you out there that take the time to post this stuff. Even an amateur can do this procedure.
Hi All, I opened my viewsonic 1912wb and found both capxcon caps bulging, i replaced the two 220uf 25v with equivalents and still no display.
The power light goes green for about 5 secs and then orange which is power save.
Should I replace all the caps or chuck it in the bin
Hi Andrew, I have a Viewsonic VA1912w (silver face) where the display blinks between two shades of black(?) I will open mine and check the caps in it, Thanks for a very informative post.
Information on the side: both Proview and Viewsonic are made in the Chimei factory, Proview monitors are the bottom of the range, Viewsonic middle and Chimei branded monitors very good quality. Chimei is a factory that builds monitors for other manufacturers, except LG and one or two others that I can't remember (like Asus started off building laptops for everyone else including Sony!)
On the inside of my monitor is a 'made by Chimei' sticker!
Thanks so much for diving into repairing a LCD monitor. I have a 24" Acer, just beyond warranty, (imagine that) that started having lines across it when I turned it on. After a few minutes the lines would get fewer and fewer and it would work fine. Someone else had the same monitor and did a step by step photo journal of replacing the bad caps. Many thanks to him too. I spent $6 at Radio Shack and my monitor is like new, even better because I put better caps in it. Thanks again
Thanks a lot I just replaced my Capxon caps with the ones that Dan used from Digikey and even with my semi sloppy solder job it worked like a charm on my old Westinghouse. Thanks again Dan and Andrew
mouser.com is a good site to buy caps and they cheap and high quality caps
Thanks to this thread I have a "new" Viewsonic vx2235wm.
They were throwing out one at work. Thanks to google and this thread, I knew what the problem was. Everybody kepted asking me what did I want that for... "I don't know".
Took it apart and went to Radio Shack and got two 1000uF caps, They only have 35volt, oh well, they're only $1.59 each, and three 220uF.
How can I pinpoint the failed capacitors? I'm having similar problems. Thanks for any help!
Generally these failed caps are detectable due to physical changes... the tops bulge outwards (they should be flat) and often dark colored discharges are visible.
To test the caps you would need something like an LCR meter. Easier to just replace any deformed capacitors.
What if no caps are bulging? Could they still be bad? My VA1912wb "died": the power light stays a sickly yellow - halfway between the orange "standby" and green "on" - when it's plugged in. No flickering, no wavy lines, just no picture, no OSD and a yellow power light.
Anyway, I took it apart, expecting to find bulging caps, but they are all clean-looking and feel flat to my finger. Do all bad caps bulge?
No, caps can be bad and show no obvious sign of damage. If you have it apart it is worth trying a few dollars of caps before chucking it.
Hi, I came across your post looking for solutions to replacing components on this particular circuit board. Except I'm not looking to replace capacitors, I'm looking to replace those 4 black rectangular chips to the left of the middle capacitor. I have no idea what those are and I've been trying to find out what they were and where I can get the components. If you know what I'm talking about and can help me identify these parts drop me an email please, thanks.
Thanks for all the great info on this topic. I too have a ViewSonic VA1912wb. It was flickering badly. I opened it up and had the two (CE101 & C200) bulging, so I replaced them. I did use ones from Radio Shack (272-1029, 220uF,35V), so I don't know how good they are and will buy ones from digikey if I need to. All other caps look good, but I'm thinking of replacing the 1000uF ones too.
So the flickering went away, but now the colors are inverted. The picture on my desktop looks negative. I double checked all connections and solder joints. All seems well.
Anyone know what might cause this? Thanks!
Thanks for this and "Fred Obermanns issue with an Acer AL2423W monitor - photos". I could not turn-on my LCD monitor FUJITSU SIEMENS SCALEOVIEW L-17. After I read this two pages I decided to try buy all capacitators of power-supply in my monitor, because I could not measure their capacity with my multimeter.
Now my monitor is working again and repair cost me +/- 100 CZK (+/- 5$).
Sorry for my bad english - I am from Czech rep.
Beautiful. Just friggin great! thanks a bunch. Took the capacitors from an old power supply that blew out last year and replaced the damaged ones on a 1905fp Dell monitor!
Took me close to 45 minutes to figure out how to open that casing. Be very careful and push in the seams from the front panel one full side at a time.
Note: You have to take both boards (PSU- Power Supply Unit and the VDU-Video Controller Unit) out in order to get to do anything on the PSU! It has two main feed cables that make things close to impossible to handle the sodering task.
Well done post!
I found your page while looking for a solution (or even a reason why!) my Proview monitor went crazy. Oddly enough I cannot find anything on the web that remotely sounds like what my poor older LCD just went through. You seem like you know your stuff and it appears you are a friendly, helpful person so I will take a chance that maybe you may have an idea.
I have a Proview 22" monitor that just recently went bonkers. lol . I had turned it and the computer completely off and went to sleep. In the middle of the night I heard this terrible loud noise. I don't know if you are familiar with the sound of playing cards in bicycle wheel spokes that we used to do as kids but it sounded very much like that. I unplugged the monitor and the sound slowly died away after a while. I then plugged it back in and within 30 seconds or so the noise returned. During this the screen remains dark and the blue power light that works when freshly plugged in until the noise begins, fades away. I wonder if you have heard of anything like this before? I am a woman but I do know how to solder and have experience with some electrical. I am thinking there is no help for it but why would it make that terrible noise when both it and the computer were shut down for the night?
Thank you so much in advance and thanks so much for helping all these people with their monitor woes!
I have heard sounds like you describe, indeed I have heard many of the bad sounds that electrical circuits are want to make.
Unfortunately the sound is not a good one. It sounds like the power supply is current limiting, thus something in the unit, or the power supply itself, has failed and created a short circuit. It is likely a fatal problem and may not be economically repairable.
Just my best guess from your description.
Andrew, like the rest, thanks your advice worked, I performed with the 470uf without looking at the cap values and it just took a minute or so for the picture to come in the first time. It started out all white, and I cycled buttons for a bit before the picture appeared.
One problem remains and that is a small rippling wave effect over the screen from top to bottom that was present before. That type of thing is similar to picture tube tv's with a 60hz hum. It has to be power filter cap. None of my caps are visibley defectived.. . Your work appears to keep on giving...well done! Jim
I have a buddy that bought two of these viewsonic LCD's one for himself and the other for his wife. About a year ago his wife's failed so they bought her a replacement. I took the failed monitor and fixed it after running across your site. There were 4 caps domed in this monitor. I also had trouble finding the exact caps locally, but did found some with the same capacitance and just a slightly higher voltage. I was able to get everthing apart and back together and the monitor works great, all for about $8 in parts.
I then found the correct parts online and ordered them, knowing the other monitor my buddy had would most likely fail. I am currently looking at that monitors bad caps, I will replace them shortly and save yet another monitor from the dustbin.
Lonnie what where the 4 caps you replaced? Andrews advice worked, I performed his with the 470uf without looking at the cap values and it just took a minute or so for the picture to come in the first time. It started out all white, and I cycled buttons for a bit before the picture appeared.
One problem remains and that is a small rippling wave effect over the screen from top to bottom that was present before. That type of thing is similar to picture tube tv's with a 60hz hum. It has to be power filter cap. None of my caps are visibley defectived.. . Jim
westinghouse desktop monitor suddenly has a "blotch?" orange/ red in color (kind of resembles a starburst or flower. Does anyone know what caused this and is ther a fix for it? Not one of the monitor buttons or desktop settings makes it go away!! HELP!! Thank you.
Thanks so much for this. I have had a VA1912 that died over a year ago, I bought a new one and that died yesterday. I was about to go and buy a new one when I thought I would look up VA1012 repair and found your page. So I dug the old one out of the closet, pulled it apart in about 5 minutes and took the card out. Now the amazing part. I live in the countryside in Thailand and have seen a young guy who works just up the road repairing washing machines and tv's. I took the board to him and he opened a tiny plastic draw with 4 capacitors in it, literally the only ones he had. Within 20 minutes he had removed the old ones and put the new ones in. Incredibly neat job. And the price for the repair... less than 3 dollars! including the caps! I took it home, had it together within a few minutes and it works as good as new.
I have VA 1912wb that died. Same problem as yours, I put new capacitors in it , but it is still dead?! Could it be my soldering? I had to go to youtube and look at soldering tutorials, I have never soldered before.....it took a bit long to get the solder to stick, so maybe I fried the board? Or should I look for other capacitors to replace?
I live 6 hrs away from a major city....in the outback here in Oz, so I try to fix things myself....
Grateful for any advice
Do a search for "DAC-19M005" on eBay and you should be able to find a replacement power supply board reasonably priced.
Hi, I experienced the same problem with my monitor, via a link elswhere on this page I read that the fuses (SMD) may be blown, sure enough a 7A fuse had blown on the underside of the board, I use a 20x magnifier to find it. I soldered an automotive blade fuse using long wires to the connections on the board and it all worked fine. Hope this helps. BTW if you can get hold of a usb microscope use it to check the board else you may end up with eye ache for a while.
Took my display apart expecting to find bad caps, and didn't.
My question: can you identify the black part in this picture, the one with circle F logo? 3/4 inch square by 1/4 inch thick. 4 pins along one edge where it mounts to board.
Display turns off, screen goes black for a few seconds, then it comes back on for a few seconds. Repeats on 10 second intervals. Until I took it apart. Now it works fine. I suspect something in the power supply is getting warm, like a circuit breaker maybe. Without the case it doesn't get hot, so it doesn't flake out. That's my theory anyway.
2006 Viewsonic VA902b
I am very grateful for your post.
I found your web page using the search terms that describe my faulty monitor.
I have this same LCD monitor (viewsonic VA 1912wb) with the trouble you described. Your post is very inspiring.
So, I followed your proceedure and was able to successfully replace the same blown as well as the failing capacitors. It now works beautifully. the caps cost me less than $5 and the repair took about 2 hrs. And the truth of the matter is that the hardest and longest part of the whole operation was in opening the clam shell case.
you saved me from both the cost of a replacement monitor as well as the feeling of guilt for sending modern electronics to the trash pit.
I have a View Sonic VX2235WM monitor that quit working so I took it apart and found that several of the caps where bulging so I replaced them and it worked great for about 3 weeks and now when you turn it on the screens goes blank after about 3-5 seconds. I can shut off the power to the monitor then turn it back on and the same thing it shuts off after about 3 seconds. I took it back apart and the caps all look fine. Any help would be greatly appreciated.
I have an acer v203h no power .. check for bulged caps no found ..fuse good wht could it be ...any advice will be most welcome thnx CoOlRe
I have an LG 117wsb, Everything else works fine except there is no display on the the bottom 1/3 or 1/4 of the screen. It started as a white band about 1/4" high and then black all the way down. Is it the panel damaged or anything else? Any help will be greatly appreciated. Thanks in advance!
Can some one please help me out, my view-sonic LCD monitor failed to power on, and i don't know where to start the troubleshooting.
Please help with any tech-information that could help.
Andrew, if a capacitor blows, does it ooze white stuff? I took my monitor apart and there is one big capacitor and two smaller ones that have oozed white stuff. I didnt want to go to the trouble of replacing them if maybe the white stuff came from something else instead of the capacitors themselves. Someone else mentioned leaking black, so I wasnt sure about the white. thx
Electrolytic capacitor contain a paste like electrolyte. Normally a white color the material is corrosive. It often turns black where it reacts with another material like aluminum.
Replace the caps. Be sure to wash hands and tools with soap and water after contact with the electrolyte.
Wow if replacing capacitors can fix multiple verticle lines on my monitor I will give it a go. Have had this problem for sometime but didn't know what to look for. Is there anything else I should check besides the capacitors?
thanks for a great informative site.
excellent post, ty - made me realise i could fix my ancient acer and being cash-strapped and time-rich this rox for me. mega thanks
Andrew, excellent page with lots of excellent follow-on posts (and it looks like you've helped lots of people!).
I have put up a page on LCD repair on my homesite (click below). I'll add a few general comments, some of which have already been mentioned above.
1. ALWAYS replace with 105 degC caps! Don't use Radio Shack caps, you'll just end up replacing them again later (assuming they don't do more damage when they fail).
2. It's OK to go up to 2x higher on the capacitance; for example, using 470 uf to replace a 330 uf. Going lower is NOT OK.
3. It's OK to go higher on the voltage; for example, using a 50 VDC unit to replace a 35 VDC unit. Going lower is NOT OK.
4. Fry's (at least the one in Renton, WA) has a good selection of 105 degC caps and is open on Sunday. If you're in the Puget Sound area, Vetco in Bellevue carries Nichicon (top of the line) and is also open on Sunday.
5. The best tool I've found for opening clam-shell cases is a putty knife. Slide the knife into the seam of the shell, then pry gently in each direction until you feel the shell unsnap. I just fixed a Dell 19" without a single scratch to the case.
Thanks for this website! It is so easy to save expensive, high quality gear from ending up in the recycler. I hope this site and others inspire people to try fixing before pitching. Keep up the good work!
my viewsonic 19 inches lcd monitor keeps on blinking continuosly and non-stop after display turn on.what had gone wrong? any advice willbe most welcome, TQ.
Thank you so very much for this detailed post. Haven't soldered yet but they are bulging lol. This will make one monitor a 42" LCD and 32 LCD TVs I've repaired. Probably a thousand dollars at retail fixed for twenty buck!
Where can I go to get a new Screen for it.. Everything else of the Monitor is just fine, just the screen is cracked on one side of it which won't let it work and of course with the device that connected to it from below included.
My Viewsonic VA902B has a problem, the left half has either some vertical multicolored striping, or is black. Once in a while is goes back to normal for a minute. I have taken it apart and wiggled ting for loose connections, but nothing happens. It does not seem to be a power issue or caps. Any idea what else it may be?
I also have a Tyris monitor with I think is a bad power supply. I found a source in China that sells UP0401UB12Q07 powerboards for $12 + $25 shipping, but I don't want to hassle it. Free to a good home, but you have to pick it up, South East Denver.
I have a Dell 1905FP and similarly to your ViewSonic VA1912wb "the main challenge was in simply getting the monitor open". As with your model "the case is a simple clamshell with a backshell and a bezel that surrounds the screen."
With the 1905FP you must first remove the stand and then remove the four screws that are revealed. Now things differ. It is the front bezel/screen that you must prize off using a screwdriver or something similar. Do not attempt to remove the back-panel as it is secured internally with four screws. Take a little care when actually separating the front bezel from the rest of the monitor as it is still attached to the control switches in the bottom right hand corner of the bezel via a thin ribbon cable. The monitor now lifts quite freely from the back panel.
Someone on Freecycle gave me a 19" dell LCD flat panel monitor. SE198WFP / S199WFP. the original owner said that it would be on for half an hour and then shut down. when i got it, i turned it on & it was on maybe 30 sec. then shut off. i took it apart & ALL the caps look fine. no bulging or leaking anywhere. so, i need to know what my next step is. do i replace the power supply? crap, i have no idea what to do next. i was REALLY hoping it was the caps... can you help me? this is the only way i would EVER be able to afford a lovely techsmexy monitor like this! i have kid's, that's where all my $ goes!
TY for your time, effort & info!
Acer lcd x223w.
Help! me please.
My acer lcd x223w used 2 year.When turn on have images, but has a sleek design wave vertical edges, about 30 seconds Mon tear itself turn off and turn on,turn off and turn on,turn off and turn on,
I am repeated all capacitor in power supply,but it does'nt work.
I have some problums to mach /replacea new lcd with old LCD,
I cannot understand the connaction of lcd
there wwires for RGB h/vertical sinc etc,
please inform me how i check the old lcd data and new LCD data
the all data sheet of LCD are available by the net but I cannot understand wich conacction to where should be connated for the new LCD
I have the same issue with the VA1912W-1 and I am going to repalce the capcaitor but i have another inquiry
I had found that I can add a DVI port, if I done that will it works?
I suspect that poor cooling is at least part of the reason for capacitor failure. The metal shields on the back of the monitors have very small holes, so before reasssembling I get the Unibit and enlarge existing holes or drill new ones top and bottom. Providing you don't leave loose metal shavings that could cause short circuits or burrs that lacerate your fingers, it can't do any harm. Lower temperatures should extend the life of all components.
I think it's crazy to send monitors to the landfill if they can be fixed for $5 or $20 in parts. Even if you don't need an extra monitor, charities that refurbish computers for needy people or schools will be glad to have it.
Hi all. I just want to know Viewsonic 1912wb monitors power supply board has one F200(M) component. what is that is it a fuse or else? please help
Just looked back at my photos of the power supply board. F200 is a fuse. If tested with a multimeter it should show a low resistance (a few ohms at most). If no circuit is found it needs to be replaced. The ratings are printed on the PCB which on my board showed 5 amps.
Yo andrew thanks 4 advise helped me alot on 2 other LCD's but nw yet again i cum 2 you all wise 1. I've got 2 dell 18 inch EP196FPf LCD monitors both got da same problem it turns on for about 5 secondes then it goes blank but there still is power the led light is on if i turn it off & on again the same 5 secondes & poof its off again but it has power. now i have allready checked for caps that are black or buldged or any sign off werdness but nothing ales looks shap plz help ow plz do
my screen just go black. when i turn if off, it will come on for just seconds.. plus i have changed the cords on the back and it seems to bee the screen.. If i keep it off, it will come on and later go out.... i have searched the net and found you... not sure what to do... this is a 5 yr old screen and not available.. got any ideas how to fix it.. thanks...a puzzled i would like to fix this...
This worked for me too! As previously reported (as as your own picture shows!) the capacitors are 220 uF - not 470 uF. I found that physically larger 100 uF 63 v capacitors laid on their side and stuck down with double sided foam tape worked fine. Thanks Andrew!
I have a Viewsonic VX2235wm. It works fine for a few hours after I turn it on, then it goes black. If I wait a couple of hours, it works just fine again, but then goes black after a few hours. And so on.
Since my monitor's symptoms seem a bit different from what you've described, I wanted to see if you think these symptoms are likely to mean bad capacitors or some other problem. I'm handy enough to solder in new caps, but I doubt I could diagnose a problem if the cause is different from the one you've described here.
Thanks for any suggestions you or other folks might have on this.
Like most of these "go black" problems, the issue is most likely in the high voltage supply used for the backlight. The test is to shine a bright light on the monitor when dark, and see if you can still see the image. If so it is a backlight supply issue.
I shined a bright flashlight on the screen after it went black, and didn't see an image. Just black screen. As I said, it works again if I let it rest for a few hours, then after a few hours of use it goes black again. Is it time to open it up and check the capacitors or is it more like to be some other issue?
Update: I opened the monitor and all the capacitors looked fine. However, there was a varistor (a blue disk with two wires) that was cracked and a rubbery white material had oozed out and solidified. I replaced the varistor, closed up the case and the monitor seemed to be working fine. However, the first time it was on for a few hours straight (three days after I "fixed" it) it went black again and now it won't come on at all.
Does anyone have a suggestion on what I can do next to diagnose the problem?
The white stuff is not from the component. It's a glue to keep some components from wiggling around and possibly causing bad solder joints. The stuff that comes out of caps sometimes looks like dried-up coke or pepsi.
I saw that white glue-like material on one of the caps. But this white oozy stuff was actually a continuous mass of stuff from the inside to the outside of the varistor. I could see more white stuff inside the crack in the varistor.
If the bad varistor isn't the problem, and none of the caps have bulges, is there anything else I can check that might be the cause of my monitor not working?
Hello, I am need of a little assistance. I have a Samsung SyncMaster T215tw and it has recently stopped showing any picture, whether it be on analog(vga) or digital(dvi) connections. For a while, it would flicker for several minutes & then the picture would stabalize for the duration that I was using it. I have verified that it is not either of the cables or the graphics card, because I can take a different monitor (still lcd) & will seem to work fine with same cables & computer/graphics card. The monitor is only a few years old and would rather try and repair than replace. I have read most of the previous posts, but before I start to open up the monitor case I was looking for similar problems & results of Samsung LCD monitors, as most of these were w/ Viewsonic & Acer.
Thank you all for your time & experience.
Fujitsu Siemens . Model ScaleOview H17-1 . Display comes on for about 5 seconds , then goes blank . Power light on front panel stays on , and power light on external power supply stays on . External power supply measures 12v which is correct . Replaced external power supply with a generic 12v 5A power supply . Monitor working perfectly . Cut open the external power supply , and found three 1000mF caps faulty inside . A bit to dangerous to safely re-seal the external power supply , so i will dump it .
I have just repaired a Hp vs19e that I got for free..... I would not power on at all. Opened it up, and I must say taking the base off was the hardest part to get access to the inside of this model. After opening it up, I noticed on the power board there was three swollen caps, 1000uf 10v. I run my own computer repair business and had many old mother boards that the bios chips have gone bad in, so plenty of caps to repair this with that were rated the same. I got it all back together and sure enough, works fine now
Other model I just repaired today was KDS brand 24". I got this one for free also, it turned on for about three min. then made a hissing noise and shut down the LCD bulbs, while holding the screen in light I could see it was still getting the display image from Windows 7. I have to say that this KDS model by far is very simple to open up, just 4 screws on the bottom of the monitor and take a tool to run around the edges of the outside to pop loose the panel. Turned out that it had a fried chip, not sure what kind it is, but looked like a flat one with two leads, and a full lead in the back of the chip. It had a hole thru it, and both 220uf 25v caps were bad that controlled the tubes. I had only one of the rated caps, had to go to ratshack to get the other, and could only find a 220uf 35v. replace the chip that was bad off a motherboard laying around, sure enough after all was replaced, it fired right up and stayed on, running for over 5 hours now, and all is good
Hello I just had my asus mk241h monitor light not come on everything hoked up properly ' other monitor works fine on pc pulled the moitor apart cannot see any bad caps on both boards inside checked inverter board seems to have power output monitor switch seems to work with my ohm meter has a16 pin conector from iverter to video input board leaning to that bord as the problem any input welcome
I have a new Acer Laptop.. With LED Display.. And well, when I view a page or picture that is really dark, the monitor seems to "dim".. and then when I view a white picture or page, you can clearly see the LEDs slowly getting brighter.. Is there something wrong? or is this some kind of special feature??
i got some vx922 screen with bad cap on the power board and after replacing the cap no more green light blinking but not display at all now black screen what else i can check ? the circuit board ?
Thanks for the info tech lesson Andrew. Just wondering if the Dell 22" Ultra Sharp 2208WFP Digital Flat Panel Monitor will have the same fix ability as your monitor had.
I haven't opened her up yet, but will try after I get a response.
What advice for this monitor do you have?
Thanks for all your help.
I have VIEWSONIC VG-2021m and it has a problem that screen is slow down like speaking or moving very slow. Like refreshing rate is some what plz do tell me how to repair it.
I had the rippling lines and horrible display. Instead of 16million colors, it was more like 256. Wow, that takes me back, but not to where I wanted to be.
Your problem above is exactly what I encountered. Two 220 uF 25V bulging capacitors. Swapped them out, and am back in business.
I have a viewsonic screen VA1912wb. My problem is the same as i have very fine lines moving horizontally on my screen. However, i have tried replacing my screen with another one. The same problem occurs. Any solutions will be much appreciated
I have a SK-19H210S 19inch TV/Monitor that I repaired the power supply with the capxon caps.
Works great now. except.
When you turn the tv it appears to turn off , the blue led goes out and the screen darkens but when measuring the AC line in it measures 46 watts/.4 amps @120vac
When the TV is on it(blue led on) measures 148 watts / 1.2 amps @120vac (blue hdmi display screen) is this the normal operation for this model ?
I have a Viewsonic VA1912wb with no image, but don't know how to open the back cover of the LCD
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