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How to repair flickering Gateway FPD 1830 flat panel color LCD monitor
One winter morning when I turned on my FPD1830 monitor, the display came on, flickered for about one second, and then turned back off. Thinking it was due to the 40 degree temperature in the room, I left it running, put a towel over it to retain heat, and let it sit for an hour while the room warmed up. Later, pressing either the SOURCE/SET button or the On/Off button forced the display to turn on, but each time, it flickered for about one second and turned back off. Repeating this several dozen times eventually caused the monitor to stay on, so it seemed like a heat (or rather, cold) issue.
On subsequent days, the room was not so cold, but the monitor still would not turn on without this long warmup time and repeated button presses. After the monitor reached its normal operating temperature (which is quite warm), it would operate flawlessly indefinitely, and could even be turned off and back on, as long as it was not allowed to cool down.
When the monitor was not working, a strong flashlight shined into or across the display revealed that the LCD image from the computer was there, so the problem was with the backlights not staying on.
If, while the monitor was operating properly, I used the OSD to turn the brightness and contrast down to zero before turning the monitor off, it was much quicker to get into normal operation the next time I powered it up. (If you have to live with this problem for a while, this workaround will reduce the inconvenience.) If I set the brightness and contrast both to 100, it was very difficult to bring up to normal operation the next time, and I had to wait longer between presses of the SOURCE/SET button for it to have any effect.
When I finally got to researching this problem on the web, it turned out that it seems to be common with the FPD1830. It was in this thread at Lockergnome Forums where I found the most useful information about it, including the fix that I employed here, which involves replacing 4 small capacitors on the inverter board.
The participants in that thread didn't mention what, if any, other fixes they had tried first. Having worked as a service technician for two years, I knew that a high percentage of failures are due to bad or failed solder connections (or cabling), so my first thought was that replacing the capacitors might have accidentally fixed some bad connections. I didn't yet have the capacitors, so it was something to try.
After reseating every cable, reheating/resoldering every connection on the power supply board and every non-tiny connection on the inverter board and all the larger connections on the video logic board, I can now report that the problem is not bad connections. It is the capacitors.
Here is a procedure for replacing them. If you have no experience repairing electronic equipment, this might be a difficult project to start with. Read the forum thread above to get an idea of the problems you might encounter. It also has some tips that should make the project go more smoothly.
Even if you are experienced, it will help to grab a few old junk circuit boards and spend several hours experimenting with desoldering techniques.
This job is additionally difficult because the 4 capacitors to be replaced are small, are nearly flush to the PC board, and are soldered clear through the board holes using, apparently, silver solder which has a high melting point. In short, depending on the value of your time, you might be better off just buying and installing a replacement board.
The forum thread refers to a MoniServ replacement inverter board that costs about $100 and is at http://www.lcdpart.com/Products/6633tza015amss.html. That page also links to a useful but reluctant-to-load PDF file with photos of the disassembly and installation, plus two alternative models of the inverter board, one a refurbished original. In the PDF, their plastic monitor case opens differently from how mine did, and the capacitors on their old board look much different from mine.
The replacement board can also sometimes be found on eBay for a low price (9/15/2010 update: I did buy an inverter on eBay, described in the note at the bottom of this page).
This was a miserable repair job, and I botched it so badly that it is hardly any consolation that the end result works. Everything that could go wrong, did.
Opening the cabinet
Opening the RFI shield
The internals of the monitor are encased in a steel RFI shield with holes in it. The two halves of this shield are pressed together and held in place with at least 4 small screws. (There are holes for more than 4.)
Removing the inverter board
There are 3 circuit boards fastened to the inside of the RFI shield. The one on the lefthand side, containing the 6 plugs you disengaged previously, is the inverter board.
Removing the capacitors
This is the hard part. First, prepare yourself to accept that if you blow this, which is not unlikely, you'll simply have to buy a replacement inverter board and install it when it arrives. It's still cheaper than a new monitor.
I will describe how I did it (and botched it), and how I think you can do better.
How I did it
I applied the soldering iron to the capacitor leg connections, and used the solder sucker to remove as much of the solder as possible. I did not realize that it was high-melting-point silver solder and that it had flowed completely through the hole in the circuit board to the other side, nor that the capacitor legs appeared to be twisted and stuffed into the holes so that they were slightly wedged (?), nor that they had been bent on the solder side of the board so that they would not easily pull cleanly out.
The result was a nightmare. Applying the soldering iron to the solder pads (and wires) on the board would not melt the solder inside the circuit board holes, so I had to resolder all the connections to provide enough surface area for heat transfer. I was then able to wiggle one capacitor mostly out by melting the solder on one leg while pushing the capacitor toward its other leg with a finger of the other hand, then repeating the process on the other leg, so that each leg came out a small amount at a time.
However, I noticed that the capacitor was coming loose due to metal fatigue in its legs, and got the bright idea that I could break off the head of each capacitor, and then pull each of the legs out while heating the solder on the other side of the board. Unfortunately, I did that to all of them before noticing that not one of the legs left behind was long enough to grasp with needle nose pliers, so I was left with little nubs embedded in the circuit board holes, and no way to pull them out. One of them came out by itself, along with the solder, when I reheated the hole with the soldering iron. Another one came out by applying the soldering iron to one side of the board while using the solder sucker against the same hole on the other side. Nice!, but the prolonged heating had made the little neighboring transistors nearly too hot to touch. Too bad. Nothing to do but carry on. There were still 6 legs that would not come out.
I tried pushing one out with a steel probe. No luck, but it made a slight hole, so I put the probe in a drill, thinking that maybe the hole could be enlarged that way. No luck there, so I tried cutting the head off a steel straight pin and put that in the drill. But the pin immediately bent over, bringing the drill crashing down onto the circuit board. No apparent damage.
At this point, I noticed that while heating one of the capacitor leads, the heat from the soldering iron barrel had melted a half moon shape in one of the plastic shields covering the transformers on the circuit board, so I removed both of the shields, which I knew I should have done before, and resumed work.
It became obvious that I was going to have to drill the leads out of the holes. I found a drill bit for PC boards and began drilling. It was going really well! Then the drill bit broke, bringing the drill crashing down onto the circuit board components. Again, no apparent damage to the board, but by this time I was starting to overheat and there was probably smoke coming out my ears. Too bad. Nothing to do but carry on.
The remaining nub of the drill bit was sufficient to drill out all six holes, plus the original two which had still not shed enough of their clinging solder to accept the legs of the new capacitors. And amazingly, the interiors of the drilled-out holes appeared to be shiny and silvery all the way through.
Carefully observing polarity, I inserted the four new capacitors, and discovered, of course, that some of the 8 solder pads had been destroyed.
The 4 capacitors are connected to the board in parallel, so I bent all their legs over each other, positive to positive and negative to negative, and made mechanically secure and incredibly ugly connections among them, and soldered them all together in two big giant blobs, and connected the mess to other points on the board that didn't have destroyed solder pads. If this sounds like desperation, it was, but it was all done under a high powered magnifying glass, so as bad as it was, it was at least not haphazard.
I tested for continuity among the parts that should be continuous, and for discontinuity among the parts that should be discontinuous, and it checked out OK. Covered the bare wires with electrical tape to prevent any shorting against the chassis, installed the board in the monitor, and reassembled it all. By this time, I was numb. I realized that it might immediately sizzle and fry, and didn't care. Oddly, though, I matter-of-factly (and numbly) did expect it to work, and it did, but it brought no joy. This worst-botch-ever was personally devastating to someone who used to be pretty good at this stuff, and I know that the board is an embarrassment that looks worse than Frankenstein's monster.
I did a web search on desoldering technique, and discovered to my surprise that some of the things I'd done had in fact been standard and recommended, as I'd remembered them to be. They simply hadn't worked in this case. That actually was a slight consolation.
How you can do better
Removing the old capacitors
I'm assuming you don't have a desoldering station with a vacuum pump. Who does?
Installing the new capacitors
The stripe on the old capacitors is the negative leg. Be sure to insert the new capacitors the same way.
Good luck, and I hope it works. From what I've seen, there have been sufficient reports of success with this fix that it appears to be the definitive solution to this problem with the FPD 1830 monitors, or at least it should be the first one to try.
I found these articles interesting. My monitor was manufactured in March, 2004:
Capacitor failures in PC equipment:
PCs plagued by bad capacitors:
Operations manual for the FPD1830 online at Gateway:
Update Nov. 7, 2007
On October 31 (Halloween, scary!), just a couple of weeks after someone emailed me about this article and I told them I'd had no problems since the repair, the backlights on the FPD1830 went out for good. I turned the monitor and computer on, saw the Windows startup screen, went into the kitchen, and when I came back a minute later, the monitor was a black screen. Turning it on and off made no difference. The backlights absolutely would not come on.
A strong flashlight revealed that the desktop image was there, so the power supply and logic were ok.
On the inverter board, one of the tiny 1mm x 2mm components, next to the line of capacitors, is labeled F1, which usually indicates a fuse. An ohmmeter across it showed infinite resistance. When I applied power to the monitor, one side of F1 read 12 Volts and the other side 0 Volts. It seems likely the inverter limped along for 6 months after my "repair" and finally one of the components I'd overheated failed and blew the fuse.
The fuse is integrated into the board and isn't replaceable. A new inverter costs $100, and would fix the problem unless the blown inverter was actually caused by the failure of something else. If any backlights are bad (they've had several thousand hours of use), they cost $12 each (there are 6). Worst case cost, $172.
So, for $2 less than that, I got a new Acer AL1916WAbd 19" widescreen LCD. It has better specs than the FPD1830, and the 1440x900 pixel display is fantastic. Its only weakness is a somewhat narrow viewing angle vertically.
I still have the FPD1830 and am hoping to try the repair again if I run across someone throwing one away or if I can get an inverter with bad capacitors for just a few dollars. Even though its 6 backlights will eventually be expensive to replace, they give the monitor a display with very even lighting and a wide viewing angle, which are useful features.
Update Sep. 15, 2010
The Acer monitor failed this month. Symptoms are about the same as the Gateway: video image visible with a strong flashlight, but no backlighting. The only difference is that the backlights don't flicker and nothing will bring them on. So I needed the Gateway monitor again while I send the Acer back for warranty service.
I bought an inverter on eBay from the seller shopjimmies. I am very pleased, and recommend them. They shipped it the next day, and my FPD1830 is working again!
The inverter I ordered was the "KUBNKM045A" style rather than the AMBIT type that was originally in the monitor. Felt like trying something new. It's the same shape and size, and the screw holes are in the same locations. One difference is that the plug is horizontal rather than vertical. There's just enough room for the plug to fit, lying flat, but it's easier to connect and disconnect than on the AMBIT. I put a bit of electrical tape between the plug and the metal flange on the power supply board to make sure they couldn't make an accidental connection. Probably not necessary.
Some readers have posted comments and reported their results in our discussion forum. One person provided a link to a YouTube video showing the repair being done.
Copyright ©2012 Steven Whitney. Last modified Sun 07/29/2012 10:52:02 -0700.