Tag Archives: CCFL

How to Fix a Laptop LCD Screen

Geek!This is Sarah’s submission for the HP Magic Giveaway. Feel free to leave comments for this article as you see fit – your feedback is certainly welcomed! If you’d like to submit your own how-to, what-is, or top-five list, you can send it to me. Views and opinions of this writer are not necessarily my own:

There can be many difficulties when fixing a laptop. Problems can arise with a laptop at any time, including with the screen. People simply buy a new computer when the screen burns out because it is too expensive to replace the screen. What people don’t realize is that fixing a laptop screen can be quite simple. In order to perform such a task as fixing a laptop screen, you have to be somewhat familiar with circuitry. Any electronic hobbyist can learn how to fix the backlight of a laptop screen.

First, you must gather the necessary equipment and hardware to perform this task successfully. You will need solder and a soldering iron with the soldering station to be able to properly set the temperature of the iron. Also needed is desoldering braid to remove excess solder; you will need an open area such as a kitchen table or workbench to be able to spread out the parts. Be sure that you are not worried about damage to the area you are working on because hot solder can damage work areas. The final equipment needed is an anti-static wrist band to prevent damage to the circuitry, screwdrivers to disassemble and reassemble the screen, and a micrometer or caliper to measure the backlight.

Second, power down the laptop and remove any power supply from the laptop; this would include the power cord and battery. Connect the grounding wrist strap to a grounding point. A grounding point may consist of metal pipes in the house or even a metal window sill; wearing this strap prevents any static damage to the circuitry of the laptop. You will now need to take the bezel or plastic piece off the front of the laptop screen. In many cases, the screws holding the bezel together are covered with rubber feet on the front of the bezel; in order to remove the rubber feet, simply take a flat head screwdriver and pry lightly underneath the rubber foot; the rubber feet are magnetically attached to the screws. Once the rubber feet are removed you can start to remove the screws from the bezel. Once the screws are removed from the bezel, take a flat head screw driver and gently pry the front of the bezel from the back panel of the screen.

Third, you will need to remove the cover plate above the keyboard. This cover plate will sometimes have the power button mounted to it as well. In order to remove the plate, you will need a flat head screw driver. On one side of the plate, there will be a small cutout next to it; this is where you place the screw driver to pry it from the laptop. Remember to be gentle; not a lot of force is needed. With some laptops, you will need to tilt the screen all the way back to remove the plate. Once this is removed, you can proceed to unplug the screen from the motherboard. In order to unplug the screen, the keyboard will have to be removed; remember that this depends on the brand and type of laptop. To remove the keyboard, you can remove several screws located at the top of the keyboard. After the screws are removed, you can gently pull the keyboard away from the motherboard which is under the keyboard. You can now proceed to trace the screen cable to the appropriate connector and remove the connector from the motherboard; some additional screws may need to be removed.

Fourth, you can remove the screen from the back panel of the laptop. Depending on brand and type of the laptop, some screens will be attached to the back panel with a few screws. If the screen is attached to the back panel, remove the screws before removing the screen. Once all the screws holding the screen into place have been removed, you can proceed to remove the screen from the back panel.

Next, you will need to disassemble the screen itself, a laptop screen, also called a Liquid Crystal Display (LCD), consists of several layers within a housing. The housing consists of a metal or plastic frame with a plastic plane located on the back of the LCD. This plane also holds the backlight control circuitry. Proceed to remove the screws from the side of the frame in order to gain access to the internal parts of the LCD. When the screws are finally removed from the side, you may have to cut the tape from the top or bottom of the LCD and frame. Be careful not to cut the wires that lead to the LCD; if these are cut, the LCD will be irrepairable and a replacement will need to be purchased. After the screws and tape are removed, proceed to find the backlight, which is located on the top and bottom of most LCDs. The backlight will have a metal casing to protect it and this can be simply pulled out without having to remove any attachment methods.

Now you will have to determine the type of backlight used. Many laptops have Cold Cathode Fluorescent Lamps or CCFLs. A CCFL looks like a miniature straight fluorescent light used in ballasts in houses and office buildings. The CCFLs are attached by a couple of wires. Turn on the soldering station to approximately 500 degrees. You will also need the desoldering braid. Use the solder iron to heat up the solder on the cable and backlight. Hold the braid to the solder on the cable to remove it. Once the backlight is completely removed from the cables, use a caliper or micrometer to measure the diameter as well as the length of the CCFL; the measurement must be taken in millimeters. You must find a company that sells CCFL backlights. One company that distributes CCFLs is Digikey Corporation. Find a CCFL that matches the length and diameter of your previous CCFL; you cannot order the new CCF until the measurements are taken. Wait for your order to arrive. Once the order has arrived, proceed to replace the old CCFL by soldering the new CCFL to the cables and place it back into the metal casing.

Finally, you can start to reassemble the screen. Place the metal or plastic frame back onto the screen; attach the screws. Before reassembling the laptop screen with the bezel, plug the screen into the connector and plug the laptop into power and power up the laptop to verify that the CCFL works. Once you have verified that the CCFL works, turn the laptop off and reattach the screen into the back panel with the proper screws. Once the screen is on the back panel, snap the bezel to the screen and back panel and insert the appropriate screws and then attach the rubber feet onto the screws. Reattach the keyboard with the appropriate screws and attach the cover plate. Now your laptop is ready to have the battery installed and power applied. Start up your laptop and enjoy your new and bright screen.