Troubleshooting Laptop Issues – CompTIA A+ 220-802: 4.8

The small form factor and mobility of a laptop creates some unique technical support requirements. In this video, you’ll learn about troubleshooting LCD video, external monitor issues, input problems, power issues, and challenges with wireless antennas in laptop computers.

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If you’re working on your laptop computer and you notice the display is very hard to read, in fact, you have to look very, very closely to even see if there’s information on the screen, then you’re probably having problems with your backlight. This backlight is what sends the light through the LCD so that you can see the information that’s being displayed on the LCD screen.

Sometimes our laptops are using LED lights, which are very reliable, and usually there’s many of them inside of your backlight to be able to send that light through. Laptops that aren’t using LED lighting are probably using fluorescent lighting, and the fluorescent lights need an inverter to invert the DC power to AC so that the light will work properly. And of course, if that inverter fails, then there won’t be any light for the backlight.

Now of course, you may be having a problem with the light itself, or even with the display, so you’ll have to do some troubleshooting to determine if you simply need to change out an inverter, if you’ll have to replace the entire display screen. If you’re noticing that the LCD display is blurry or it’s fuzzy, or perhaps some of the text looks a little bit blocky you when you compare it to other text on the screen, then you’re probably not running at the native resolution that LCD display.

In that case, an easy fix would be to change the configuration of your Windows environment to match the native resolution of the LCD display you’re using. So you may have to access the manual for the laptop to determine exactly what that resolution might be. If the laptop display is flickering, or there’s a motion on the screen whenever you’re moving the laptop, you may have a problem with the cable or the connector that’s going to the video.

We’re opening and closing this laptop all the time, and that causes stress and changes things with the connections that are inside of the laptop. So you might have damaged the video connection, or you may just need to reseat the video connections inside of the laptop. We don’t always just use our LCD screen, of course. We might be in an office where we can plug into a much bigger display, so we want to be able to access and use that display.

And very often, we have to tell the laptop that the display is actually connected. So there’s usually some secondary function keys on your keyboard that allow you to redirect that video signal, and you might get a little display that tells you exactly how that video signal will be used. We can usually see this to plug into an external monitor.

We can go there to bypass the LCD that’s on the screen itself, but it’s always going to use that video hardware that’s inside of our laptop. So plugging in this way may also be a good way to troubleshoot the LCD screen that’s on our laptop computer. If you look at the keyboard that’s on your laptop, you’ll usually find a secondary function button, and there will be another key that refers to an LCD display, an external display.

It might be an icon on your screen. On my computer, my function key is down here on the left side, and the F8 key here at the top, you can see is lightly blue, which indicates that is a secondary function for the F8 key, and I would hold down Function and F8 to change between my internal display and an externally connected computer display.

Our laptop keyboards are very delicate. Underneath there, there’s some very tiny pieces of plastic. And if you ever need to remove the key cap, you want to be very careful that you don’t break anything. If you’re not quite certain how to remove it, make sure you check the documentation for your laptop so that you don’t cause any problems.

One thing that many users run into when they’re using a laptop is they’re not accustomed to having this mouse control pad right next to the keyboard, and they might be typing and accidentally hit that with the palm of their hand. And suddenly, the cursor moves dramatically on the screen.

Sometimes you can minimize this by changing the configuration of that keypad itself, and you can remove that ghost cursor or from moving around the screen when you aren’t actually touching it with your fingers. Sometimes you can also update the driver of the mouse pad to be able to limit this from occurring, because the new driver may be looking for things like a palm press rather than a finger tip press on the mouse pad.

If somebody’s using their keyboard and they’re finding that the keys are not putting in the words or the letters that they need, and instead numbers are coming up, then it may be locked into a numeric keypad mode. Most laptops are too small to have a full size numeric keypad, but if you look at this laptop screen, you’ll see this has secondary keypad screen set up as those function options.

So if the function key gets into a locked in mode, you may find that instead of these letters popping up, instead of a letter U, you might, for instance, get a number four. So make sure that you’re not locked down. If somebody’s having a problem typing on their keyboard, it may be something simple that’s configurable in the software of your computer.

From time to time you’ll find a laptop where the battery is simply not charging, and in most cases it’s an older battery. And after a while, our batteries wear out. They are not able to hold a charge any longer, and we’re not able to charge them up at all, and simply replacing the battery will be the fix for that particular issue. Sometimes the charging hardware that’s inside of your laptop is faulty, and it’s not going to charge any battery at all.

So you may have to troubleshoot to determine if your problem is with simply the battery, or if it’s with the hardware of your laptop. If you’re not getting any power at all to your laptop, you might want to check the power supply, that’s usually this external brick adapter. Make sure that it’s sending signal or power or into your computer, and you can check that very easily with a multimeter.

Sometimes the laptop is the thing that’s causing the problem. Perhaps it is hung, and it needs to be completely reset. And most of the times you can do this by holding down the power key on your laptop for an extended period of time, maybe 10 seconds or 15 seconds. You may want to check with your manufacturer’s documentation for your laptop, because there are other methods used to be able to do a master reset of the laptop.

If you have the ability to look behind the front bezel of your laptop screen, you would see a lot of wires that were wrapped around the edge of that. Most of these are for your wireless networks, like your attitude out 802.11 wireless or your Bluetooth connections. They’re all wrapped around there so that when you open up the screen, they’re as high as possible.

You want to be sure that if you’re ever working inside of your computer and doing maintenance, that you don’t accidentally disconnect any of those wires. You can disconnect them very easily from the wireless cards themselves. So if you’ve now restarted your computer and you’re suddenly not seeing your wireless network anymore, it may be because you accidentally disconnected your antennas.

Here’s where you might see this. This is an 802.11 adapter that I’m installing into a laptop. You can see there’s other adapters for the modem, for instance, right here. This has not been pushed all the way down yet. I have to push down this particular adapter, and here are the tiny little antenna wires right here. So I’ve got a main connection and an auxiliary connection that I would plug into.

It’s very easy to forget that step, and they’re very small. They’re very easy to miss, so you want to be sure that once you power things back on and you’re not getting signal, you want to come right back to this connection and see if there really plugged in solidly, or if you even remembered to connect them to the adapter at all.