In this article were going to disscuss Laptop Screen Types: (CCFL and LED discussion), and Repair Methods. Including LCD Bulb Replacement, Power Inverter Repair.
Laptop screens today will use one of two common lighting systems. Both are still considered LCD Screens because they are. The Image to the screen is Liquid Crystal Display; it is only the lighting that will change for these 2 types.
LED light on a laptop is newer technology because all screens used to use only CCFL bulbs. The CCFL bulb is a thin glass tube with a protruding metal pliable rod on either side. Wires are soldered to both ends of the bulb then attach to a plug that will plug into the power inverter… You will need to solder the wires to the ends if you ever need to order a replacement bulb. You can however usually find replacement bulbs that come prewired with plugs also attached. You get the same size bulb as your screen specs specify.
When disassembling the screen, you will start by removing the power inverter if it is attached. You will notice that all screens are framed with a thin metal frame. This helps to hold all the screen parts together it also helps by framing the front screen glass panel in and protects the glass edges from harm. You are going to use a Razor Blade here to help separate this metal frame from the rest of the screen.
This frame wraps from the front of the screen panel to the top of the panels edges all the way around the screen. Most screens will have 1 or several pieces of tape that cover the frames edge. You need to run the razor blade edge between the seam of the screen frame and the aluminum bulb backing plate. To do this you will flip the screen to its back side and start at the top of the screen, running the razor from right to left. Be very careful not to cut the LCD bulb wires or scratch any of the screen panels. The sides of the screen will usually have securing tape that you need to either peel away or carefully cut to separate the front metal frame.
Once you have cleared any securing tape, you will now be unsnapping the metal frame away from the screen panel. You will need a Plastic Pry Tool assist you in removing the frame. The best tool would a guitar pick. You need to start at the top. It is imperative that you do start at the top of the screen when removing the frame because you are not completely removing the frame (you can, but it is not needed to change a bulb).
You will wedge the pick in between the seam of the frame and screen panel top side. Slightly pry upward near one of the imprinted tabs on the frame and push outward away from the front of the screens glass panel. Do not force this frame away or you might crack the screen. Go Slow, Have Patience and you will easily be able to separate this frame… Slide the pick back and forth from the right side end of the frame to the left end side. Then you can do the same to the sides, though start from the top and work your way down the sides pushing the frame away while you are going… The frame will fall in front of the display panel (not literally ―fall‖). You can now, either, pull the frame away and set a side, or you can leave it attached to the bottom framing tape but just flip it down on the table while holding the screen up at a 90% angle.
You will now see an aluminum bulb guard on the rear upper side of the screen. This can sometimes have a micro sized screw on each side so look real close for one and remove it. Now, right where the screw you just removed was, flip the screen to the side and parallel with the bulb guard screw will be a screw on the side of the screen again it will be a micro sized screw and will need to be removed, the same goes for the opposite side of the screen, then again there might be a second screw on the side of the screen towards the bottom of the side. Some will have these and some will not.
The object now is to pull this metal bulb tray up and away from the screen to swap out the bulb. There will be a few things you will have to do before simply lifting this metal/aluminum tray away from the screen.
The red arrow shows the metal bulb tray and the blue arrow shows you will be sliding it outward to remove, after you free the LCD wires.
Remove any tape that is securing the LCD bulb plug wires to the screen bottom side (usually a piece of thin yellow tape). You should now see a white tab that the wires track through. This wire white tab/holder is attached to a thin plastic rail that runs horizontal along the top front of the screen and will be stuck to the screen using sticky double sided tape strips. What I do here is use a pry tool and gently lift up on the white small tab securing the wires… lift it up to a 90% angle and you will be able to pull each wire out of the track and away. One wire is short the other long. The long wire will be stuck to the thin horizontal plastic strip that runs along the top front of the screen, you simply will pull on the bulb wire to release it from the track along the front; it should peel right off. You should still have that small white plastic wire tab sticking up in the air (90%), and you will want to use that as a pull tab to pull the tab itself and the horizontal plastic bar away from the screen panel and metal bulb tray… The goal it to allow free space to slide the metal bulb guard out and away from the screen.
You will use a fingernail or a plastic pry tool to push the metal bulb tray upward, start on one side then slightly slide it a little bit, then go to the opposite side and slightly lift it, alternating until it is free from the screen. Be very careful when doing this otherwise the bulb will break (though it is already broke which is why you are changing it). Once you have the metal bulb guard free, set the screen aside. The bulb guard will have the bulb still inside its tray, there is actually a smaller metal tray inside the large metal tray, you can go ahead and separate these trays from one another now. Look at both ends of the LCD bulb… this is typically where a bulb failure will occur (at either end). Either the wire will overheat and will break, or it will deteriorate the wire to a very fragile state so that if you were to wiggle it slightly it would snap and break. Look at the very ends of the bulb too, a faulty bulb usually shows a blackish color at the end or both ends… this is due to internal bulb heat… which is why laptops can have color wash-outs (pinks, oranges, reds) to where the whole view of the screen when illuminated has a pastel transparent colored tint to it, the tint can change colors as well, and you can sometimes hear a faint buzzing noise from the bulb. Flickering of the light on and off is another signal that the bulb is failing.
Once again, look at the bulb ends (you should have only the smaller metal bulb guard and the bulb in front of you), there are white rubber caps on each side covering the LCD bulb power posts. These are there to keep the post and wire grounded so the screen doesn’t short the bulb. You do not want to lose these caps… they are not glued on, they only slide on, and can easily fall off, so be very cautious. You will use a plastic pick or pry tool now to push the actual LCD bulb out of the small metal tray/housing. Notice here the placement of the bulb wires at both ends, notice that they do not protrude straight out the back end of the bulb? No, they are bent to a right angle (90%) at the end of the bulb and are capped with the white rubber plug, they also bend towards the front of the metal tray, not the top, not downward… they do this for a reason… they do this to allow it to properly slide back into and out of the small metal tray/guard then slide back over the screens glass panel when reassembling so that the wires are both out of the way and ready to re-stick along the top front plastic rail.
So, when replacing the bulb, you will make sure the ends are properly recapped with the white grounding rubber caps and that the wires are placed facing the correct direction for reassembly. If you need to, take photos while you work to be able to remember assembly and reverse process.
The Power inverter is the only part left for screen repairing.
You can only do so much to repair the inverter if failure occurs. The only thing I have found that works about %60 of the time is to change the transformer block on the Inverter. It is the part with the copper wire wrapped all around it… a long
rectangular shaped component with legs on both ends (usually 2 to 3 on one side and 2 to 6 on the other – the legs attaching to contact pads on the inverter board. You will need to use a soldering gun and flux paste.
To replace a cracked screen (or what ever the issue…) you can order the screen by the model number of the laptop, but I do not recommend doing so and it is the Lazy way to replace it.
Not only is it not correct, it could harm the laptop by possibly installing an incompatible screen. You need to realize here that not all screen vendors will send the exact screen you need and will sometimes replace with the closest compatible screen, even swapping stickers/labels… I’ve seen it all…
The way you should be replacing / ordering the screen is to remove the screen, then look at the white large sticker on the rear side of the screen. It will tell you the exact part number of the screen, it will also show you the type/model of screen. These numbers/letters are important in ensuring you receive an exact replacement part.
The replacement screen part replacement number will almost always include the screens size in the number.
Here is a typical screen part order number: LP173WD1 HD+ (TL) (A2) 17.3”
Notice in the number that the screen size is in it (LP173), you will find this in most all screen numbers. Now, notice the (TL) and the (A2)… this is very important that you replace with the same exact numbers. If you don’t, you are risking damaging the laptop, or the screen simply will not work, it will show grey color or a white-out.