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There are hundreds of small technical malfunctions that can frustrate the best of us each day such as the burned out lamp that once illuminated your car radio, or that sputtering fluorescent light at the office. One of the very worst is when the display on you laptop computer begins to darken and dim — or simply die.

You call the manufacturer and hear that they will be happy to replace the entire display module, but the cost could be as much as $1,000. You check with local computer service technicians who estimate that fixing it will cost hundreds of dollars. You might consider just chucking that computer (after all, it is two years old) and buying a new one. But then you think about all the problems of transferring your files and software without an illuminated display to the new machine, cringe just a little and decide to try something else.

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Faced with a significant financial outlay, you log on to the Internet and start searching for less-costly alternatives. The first site you find opens to an urgent plea from another user with a similar problem:

"I have a (name brand) laptop with a 13.3″ display. I rarely use it because I can't see the screen. There is still a display but it is extremely dim. I have to take it into a darkened room just to see it. The manufacturer will replace the entire display, but the cost is prohibitive. Does any one have any other ideas?"

What follows is normally a half dozen empathy-filled responses from other users with the same problem whose suggestions range from using the laptop with an external monitor to a series of keyboard fixes that may or may not work. And, this scenario is repeated a hundred times a day by computer user groups, desperate laptop owners and anxious technicians, all seeking a better solution at a fraction of the cost.

Keep this in mind: a liquid crystal display for an individual's laptop is virtually identical to the LCD used at a 1,000-store grocery chain or your local department store. The problems are just dramatically larger and significantly more expensive.

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It may come as no surprise that many problems with dead or dying laptop displays could be resolved by simply replacing the miniature fluorescent lamp(s) that backlight the liquid crystal display. It requires a certain degree of boldness, a basic knowledge of electronics and a few simple hand tools. But in many cases, the problem can be remedied in a matter of less than an hour and your display will glow like new.

The LCD itself is a very rugged device, but it has an Achilles' Heel. It must be illuminated by miniature fluorescent lamps that evenly backlight the screen. The lamp (there may be two) is powered by a small inverter which plugs into the board on one end, and is connected to the lamp by a wiring harness attached to both ends of the lamp. Lamp failures can occur from anything: a sharp impact like dropping your case or simply by extended use. Unlike Achilles, your laptop need not die from this "wound" because it can often be repaired to like-new condition for well under $100 and often much less.

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The three most common problems that cause the failure of liquid crystal displays are the fluorescent lamp itself, the connector for the DC-AC lamp inverter and/or the high voltage wire connecting the inverter to the lamp.

THE LAMP — The glass used in LCDs has been standardized on 13.3″, 14.1″, 15.0″, 15.1″ and 17.0″ screen sizes. However, the miniature lamps that backlight these displays can have as many as five or six diameters depending on OEM design options. This makes replacement and service problematic.

THE INVERTOR CONNECTOR — For individual LCD repairs, the connector may be removed and reattached. For multiple systems, one must make certain that the proper interfacing connector is used to avoid mismatching or requiring a patch cable. And, each manufacturer uses a different connector.

(click image to enlarge) THE HV WIRE — Common PVC-jacketed hookup wire is not sufficient to efficiently drive a miniature fluorescent lamp. Silicone insulating wire conforming to UL 3239 is best suited to most applications. Though often overlooked, consideration of wire type and geometry is important because inverter output for lamp ignition is 1,500V rms and operating voltages exceed 500V rms.

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The most common difficulty in replacing a laptop's backlight is lack of standardization and perceived availability. There is little commonality in the application of miniature fluorescent lamps used to backlight the great majority of liquid crystal displays.

Industry's drive and consumer demand to make a lightweight, ultra-slim laptop has driven fluorescent lamp diameter smaller and smaller. And unlike an individual, a service department keeping thousands of systems running must be concerned with parts inventory, availability and cost. A $400 display may only need a $15 lamp assembly to be fully functional, but traditional wisdom has been to replace the entire assembly. And the same has held true for laptop manufacturers.

Diagnostic or failure mode analysis also consumes expensive technician time so module sub-assembly or component assembly replacement is simply easier. But that doesn't help you. You still need a reliable source to get the right fluorescent lamp for your laptop.

A man named Rick wrote back to that frustrated user with his dim laptop, giving advice that you can use as well. "Here's your dimming screen problem answer. I just repaired my (brand name) laptop which had the dimming, pinkish and dark screen problem everyone is reporting, and I have the simple solution that no one at a multi-million dollar company can seem to tell us. With a little research on the Internet, a soldering iron and nerves of steel, I fixed the machine myself."

"First, carefully open your display module. At the bottom is a small fluorescent lamp which lights the screen. A small inverter powers it, but it is unlikely that it is bad; most often it is just the lamp. Just remove the failed lamp and install a new one. Of course, this is much harder than it sounds, but if you don't have the nerve to do it yourself, have a tech do it. If you don't have a soldering iron and don't know how to use it, don't do it. Be sure to use an anti-static pad if you decide to do it yourself."

"Here's the problem and the solution, and it will save you the cost of a new screen or a new computer:

The Problem — Most repair shops tell you they cannot just get a fluorescent lamp and they try to sell you a new $1,000 display module.

The Solution — You can order the replacement lamp (measure its length and diameter) for about $10 each plus shipping. Get two in case you or your tech breaks one.

So for $10 for the lamp and whatever the tech charges you to repair your machine, you will be back up and running."

There are many reputable lamp and inverter suppliers and distributors. Choose a company with a solid reputation and verifiable credentials because the price of failure is not worth the cost of cutting corners. You will need a torque screwdriver, soldering iron, copper foil and lots of patience.

First, carefully open your laptop and disassemble the display so you can access the rear. Be aware of the problems of static electricity that could damage your computer, and use an anti-static pad or equivalent. Carefully remove the fluorescent lamp (it is probably plugged into a wire harness and held in a metal rail with end caps). One caveat: Save the end caps and harness used with the failed lamp and you maybe able to recycle them. Measure the lamp's diameter and length. Be sure to have the name and model number of your laptop.

Go on the Internet and type in a keyword like "LCD Backlighting" or Miniature Fluorescent Lamps." In minutes, you can be ordering a lamp that matches the one you have just removed. Many companies also offer assemblies that can include the lamp(s) end caps, high voltage wiring, DC-AC inverter and connector if you wish to replace the entire lamp assembly. Incidentally, high volume tech centers often do this as a matter of practicality, and they still realize savings of over 75 percent against entire module replacement.