You wake up one morning, open your laptop screen, just to find it black, but the computer is clearly powered on because you can hear the noise from the fans. Panic sets in quickly as you wonder what’s wrong. If you look very closely you can see a weak outline of what’s on your screen, and if you shine a flashlight on it, you can almost figure out all of the images and text.
This is a a natural problem with laptop screens, and typically only has 2 likelihood of the cause: the screens back light is now bad, or the trunk light’s inverter is now bad. The trunk light is actually a fluorescent light that sits behind your screen and lights it up enough to see everything clearly as you normally should. These lamps can go dell inspiron 3511 south occasionally, causing your pc’s screen to go black, and only show a weak outline of objects. The second possible cause, the trunk light’s inverter, has the same appearance when it goes bad as the back light itself does. The intention of the inverter is to convert your laptop battery’s DC power back to AC power, which is required because of your back light to work. If the inverter goes bad, the proper voltage will not be supplied to the back light, thus not highlighting it, causing a very poor screen. Sometimes, there are ways to determine whether it is your back light the culprit, or the inverter the culprit, just by the way your screen acts. Typically, when a back light goes bad, it will not illumine at all, or it will illumine the screen in a reddish colored hued, which might stabilize as you continue to use your laptop, it is an easy task to detect if you’re experiencing and enjoying the reddish colored hued by lording it over out the video card. To exclude the video card, simply plug in an external screen to your laptop’s VGA port that is on the back or side of your laptop. If after pushing into an external monitor you do not see any color distortions as you did before, you know that your back light has to be replaced, if you still see the same distortions on the external screen, your video card is damaged. When an inverter goes bad, it’s quite common for it to gradually get worse first, and your screen may stay lit for a brief period of time prior to going poor, and then will re-illuminate after rebooting, just to go poor again within a few days. However, these are not rules that alone should be followed to provide an accurate analysis. Rather they are more of commonly experienced symptoms. To provide an accurate analysis, you must test your inverter and back light. There are special tools that are for testing the inverter, but they can be rather expensive. Also, I would not suggest testing the inverter with a multimeter, as the voltage given by the inverter can be rather high.
First of all, in order to test your back light and inverter, you must have another laptop that has a fully functioning screen you don’t mind opening. They do not need to function as the same model or even brand, as the connectors are generally the same on all laptops.
Now, you must access to your laptop’s screen. To do so, eliminate the plastic prop covers around the screen with a flat head screwdriver, and place them glue side down on feel paper to preserve the glue. Next, remove all of the screws around the screen and place them aside in a safe spot. Do this and the next step to the laptop that works that you are using to test the damaged one.
Next, run your finger underneath the bezel, everywhere over the screen to remove the bezel.
Once you have removed the bezel, you should see a small board attached to the bottom of the screen with at least 2 cables taken from it. This is the inverter. One cable comes from the laptop base and DC power to the inverter. The other cable(s) emerge from the screen, and hook up to the trunk light(s). If you see more than one cable coming from your screen connecting to your inverter, this means your laptop has multiple back lights.
Once both your damaged laptop and testing laptop’s screens are exposed, we will test the inverter on the damaged laptop. To do so, on both laptops, eliminate the cable(s) going from each screen to the inverter. Do not eliminate the cable going from the laptop base to the inverter. Place both laptops very close to one another and plug the trunk light’s cable on the damaged laptop into the test laptop’s inverter. Turn both laptops on. If you can see everything as bright as normal on the damaged laptop, and it doesn’t go poor again after a brief period of time, you must replace the inverter on your damaged laptop. At this point you’ve finished the diagnosis of the problem, and don’t need to go on deeper with this article. If the damaged laptop’s screen is still poor, and you can still see just a weak outline of the objects on the screen, your back light(s) must be replaced.
However, we don’t want to stop there. We must also test the inverter on the damaged laptop to make sure that also doesn’t need to be replaced. To do so, first make sure both laptops are put off, then unplug the broken laptop’s back light plug from the test laptop’s inverter. Now, plug the test laptop’s back light into the damaged laptop’s inverter. Turn both laptops on. If the image on your test laptop’s screen can be as bright as normal, this means your inverter is okay and doesn’t need to be replaced. However, if your test laptop’s screen is now poor like your damaged laptop, the inverter on your damaged laptop must also be replaced.