Introduction: Repair a Flatscreen Monitor for $15


I found an LCD flatscreen monitor on the sidewalk. Took it back to the lab, turned out the screen was pretty dark, especially on the bottom half, so I figured the backlight was broken. I opened it up and found this to be true. turns out one of the two outputs of the power inverter that fed the two backlights was broken. I had a set of CCFT lamps + inverter ($15--> lying around from a previous project (lighting a sound proof temperature controlled experimental box) so I decided to pop one in. Here's how I did it (it worked great).

Step 1: Open It Up Carefully

FIRST OF ALL, BE VERY CAREFUL, THE CCFT LAMPS CONTAIN MERCURY GAS WHICH IS VERY POISONOUS. I take no responsibility if you are in any way injured by mercury gas or any other procedure described in this instructable. To be safe you should do this outdoors or in a very well ventilated area in case the lamps break.

having said that, open the monitor carefully. There will probably be at least two or three weird overlapping wire connections (see picture) which you'll have to carefully unplug to get everything apart. Inside you'll find the LCD screen, a thick glass/plastic light diffusion panel, some thin plastic light diffusion sheets, and two CCFT (cold cathode flourescent lamps)backlights (at the top and bottom of the LCD screen).

Figure out which lamp doesn't work. This may be because the lamp itself is dead, or because an inverter output is dead (the lamps use AC which is converted via an inverter from the DC sent to the monitor). These lamps take high voltages, if you plug in the monitor to figure out if the lamp is broken be careful.

Step 2: Put in Your Lamp

buy a CCFT kit from allelectronics or some other place ( If the lamp will fit in the monitors case without obstructing any of the other pieces (the light diffusion glass/plastic, or anything else). Then you're set, just pop it in and secure it somehow.

In my monitor, there was barely enough space between the light diffusion plastic and the case wall to put in my lamp so I had to cut up the case a little bit.

I also put a strip of cardboard behind the lamp to elevate it to the level of the light diffuser, otherwise it was too low.

Step 3: Test It Out

you should be able to test out the monitor with its new backlight(s) without putting the case back on. If you can't get it plugged back in to a computer to test the LCD + lamps, then at least test the lamps behind the LCD (without the LCD turned on). Just to see if they illuminate well in the position to placed them.

In the picture below I'm testing out only the bottom lamp I replaced. Works well.

Step 4: Put It All Back Together

put everything back together. This can be a pain cause of the overlapping plug connections. Make sure to dremel a little notch on the outer case so you can snake your lamps inverter cord out (the inverter will have to have to be powered by a seperate power outlet).

Make sure you don't forget to put all the pieces back in (I forgot some and the ommision makes my LCD slide around a bit)

Step 5: Test the Whole Thing Out If You Haven't Already

test it out plugged into your monitor. See the with and without replaced lamp picture below.