Troubleshooting Laptops – CompTIA A+ 220-1001 – 5.5

| March 26, 2019


Laptops have unique considerations when troubleshooting issues. In this video, you’ll learn about laptop display issues, input problems, wireless challenges, and more.

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If you’re having problems seeing the display on an LCD monitor or the display is very, very dim, you might be having a problem with the backlight. There’s a light behind every LCD display that is shining through. And if there’s a problem with that backlight, we won’t be able to see the image that’s on the screen.

If the backlight is completely out, you still might be able to make out some of the images on the screen. It helps to look very closely or to use a flashlight to try to see any images that might be on that LCD display. If you’re not getting any backlight and you’re using the older fluorescent style lights, you may have to replace these inverters to get those fluorescent lights working again.

If you’re getting a completely black screen and you’re not sure if the issue is related to the video card or if it’s related to the LCD display, you might want to try connecting an external monitor. If the external monitor is showing the information from your laptop, then the issue is probably not with your graphics subsystem. If that’s the case, we may have a bad LCD display inside of the laptop, and that might need to be replaced.

Our laptops take a lot of abuse. We re them from place to place. We’re constantly opening the display and closing them again. And because of that, we may find that some of the connectors may become damaged or loose.

If the video’s flickering on your laptop, you might have a connector problem. This may require that you replace a bad video cable or replace the bad video hardware that’s connecting that LCD display to the motherboard of the laptop.

It’s very easy for debris to get underneath the keyboard of a laptop. And if you’re having keys that are sticking, you may need to clean out that keyboard. You do have to be very careful on most laptops. Those key caps are very fragile. So be very careful if you’re planning to clean out any part of those keys.

Another problem that you might see would be related to the mouse pad. If you’re not touching any part of the laptop and yet you see the mouse slowly moving across the screen, then you have what we call a ghost cursor or pointer drift. And this is caused when there are issues with the mouse pad itself causing the cursor to bounce around the screen or to move without you providing any input. Another issue you might find is when you’re typing on your laptop and you find the mouse moving around because your palm happens to have pressed the mouse pad.

One way to solve both of these problems is to update the mouse pad drivers. The drivers can constantly check for any type of drifting of the mouse and can recalibrate the mouse pad so that does not occur. The newer drivers may also be able to differentiate between you using your fingers to move the mouse around with the mouse pad and you inadvertently hitting the mouse pad with your hand while you’re typing.

One of the challenges you have with a laptop is there’s a limited amount of space on that keyboard. So there’s not usually an independent set of numbers that you can use on the side. In those cases, the laptop may have a certain grouping of keys that are doubling both as letters and numbers. And if you inadvertently turn on the Num Lock, you may find that instead of typing letters, you’re suddenly typing numbers.

If you look closely at this keyboard, you’ll see there is a Num Lock key at the upper right. You’ll also notice there are a number of keys that have a letter and a smaller number that is listed here in a blue color. With the Num Lock selected, whenever you press those particular keys, you’ll have a number that appears instead of the letter.

You can choose to type these numbers by holding down the Function key and pressing the number. Or you can press Num Lock and then you don’t have to hold down that Function key. But you have to remember to press the Num Lock again to turn it off so that you can go back to typing letters.

There are many different antennas inside of your computer. And they’re usually running around the top of your LCD display, since that tends to be the highest point whenever you’re using your laptop. You may see a number of different antenna wires inside of your computer. You might see Wi-Fi main, Wi-Fi auxiliary, Bluetooth, and others. When you’re working inside of your laptop, it’s very easy to accidentally disconnect one or more of those antenna wires.

So if you’re working inside of your laptop, even on something that may not be related to any of these antennas, make sure you check those connectors before closing up your laptop. If you do close everything up and there’s a missing antenna wire, you’ll see that there’s no signal available on Bluetooth or no signal available on your Wi-Fi. And you’ll have to go back into your laptop to reconnect all of those antenna wires.

Here’s a close-up of those very small antenna connectors on this Wi-Fi card. And you can see here are the antenna wires waiting to be installed onto that adapter.

We rely on the batteries inside of our laptops to provide us with the mobility that we need when we’re away from a power source. But if you’re finding that the batteries are not holding the charge that they once did, that’s because those batteries do lose capacity over time, and you will eventually need to replace those batteries. If the batteries aren’t charging at all, it could be that the battery is having a problem. But it could also be that the charging hardware inside of your laptop could be the problem. You may want to try charging that battery in an identical laptop to see if the problem is related to the battery or if it’s related to the charging subsystem in your laptop.

If you’re connected to an external power source with your laptop’s power supply and you’re still getting no response from the laptop, then you may want to grab a multimeter. This will allow you to check the AC power on the outlet to see if you’re getting the proper amount of power. And you can also check the DC power on the other side to see if it’s providing the laptop with the proper voltage as well.

It might also be that the laptop is hung and needs to be reset. In some laptops, there’s no way to remove the batteries inside of the laptop so usually you would hold down the power button for a certain amount of time. Or there might be a set of keystrokes on the laptop that provides a hardware reset. You should check the documentation of your laptop to find out which you should use to be able to reset that laptop.

If you’re used to only using the internal LCD display on your laptop, connecting to an external display can sometimes be confusing. There are usually function keys on the laptop that can control how you’re sending a video signal out to that external display. Usually it allows you to cycle through different configurations. You may have one configuration where you’re only displaying the video on the laptop and not on the external display.

The other option may be that you’re duplicating or mirroring the image for both of those. You could also have your laptop on one display and you’re extending that display to the external monitor. Or it could be that you’re only displaying this information on the external display.

One very common way to force the video signal to go to the external display is to completely power off the laptop, connect the external display, and then power on the laptop. The default for many laptops is to automatically use the external display if it recognizes one during the boot-up process.

On one of my laptops, I have control of the external display with this F8 key. And you can see the blue Function key for the the CRT/LCD setting. So I would hold down the Function key, press F8, and I would be able to cycle through all of those different settings for sending a video signal to an external display.

Category: CompTIA A+ 220-1001

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