Troubleshooting Laptops – CompTIA A+ 220-901 – 4.5

Unlike a desktop computer, a laptop has unique hardware and software troubleshooting requirements. In this video, you’ll learn how to troubleshoot laptop-specific issues.

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Our laptop computers have an LCD display that’s able to show us the output from our laptop computers, but sometimes we’ll run into a situation where there’s no display, or the video is very, very dim, very difficult to see– barely perceive on the LCD display. What we’ll want to do then is verify that the backlight is working. We want to see that that bright light is being shined through the LCD display, because of it is in we may not be able to clearly see what’s happening on the screen. If we have an older laptop with fluorescent lights behind the LCD display, then the problem may be with the inverters and they may have to be replaced.

One way to test the video capabilities of the laptop without the LCD display is to plug in an external monitor. Then we’re able to turn on the laptop and see if we see a normal display on the external monitor, or if the problem is still a black screen instead of seeing the normal output. If the external display is also completely black, then the problem might be with the video adapter or the system board that’s inside of the laptop. If we see a normal display on our external monitor, then the problem may be specific to the LCD panel that’s inside of our laptop. There’s usually a very thin ribbon cable that runs the video signal from your system board on the laptop across the hinge of your laptop and onto the LCD display, and opening and closing the display a number of times can create wear on that particular cable. This may be a connector issue or the ribbon cable itself. It might be bad video hardware, as well. So if you’re getting flickering, or the screen is not looking the way it should, you might want to check all three of those things to see what the status and connectivity might be between the system board and the LCD display.

The keys that are on a laptop computer are not quite as durable as those you might find on a traditional keyboard. If you do have some sticky keys that need to be cleaned, make sure you’re very careful during the cleaning process that you don’t break off any of those key caps. You may have a situation where the mouse cursor on your screen tends to move without you actually touching anything. This ghost cursor– or pointer drift, as they call it– is one that can be very frustrating, so you want to check and make sure that you’ve configured your palm rest so that the touchpad is not going to register when you’re not near it. Or you may want to update your drivers and make sure that the operating system is using exactly the right drivers for your hardware.

You might also see the situation where you’re typing normally on your laptop keyboard, but instead of seeing the letters on the screen, you’re seeing numbers. That’s usually because our laptop keyboards will double as not only a normal keyboard, but also a numeric keypad. You can see on this keyboard that there are blue numbers associated with the letters and the numbers on the normal keyboard. It could be that you’re inadvertently pressing the Function key and enabling that secondary capability, or there may be a function lock on your keyboard that permanently enables the function capability so that when you’re typing, instead of letters appearing, you’re seeing all of the numbers that are associated with the letters that you’re pressing.

It’s very common for our laptops to connect to 802.11 wireless networks and Bluetooth networks as well. There are wires that are used as the antennas for these wireless networks that run through your computer and around the outside of your LCD display. There are very small connectors on the ends of these antenna wires, and it’s very easy to accidentally bump them or move them whenever you’re working inside of your laptop. This is often a very quick fix– there’s usually a panel on the underside of your computer that allows you access to these adapter cards so you can easily open it up and see if any of these wires happened to have come off of these main connectors on your wireless or your Bluetooth adapter cards.

If you’ve had your laptop for a year or so you may notice that the laptop battery doesn’t seem to be able to hold the charge that it used to. That’s because the battery technologies that we use tend to lose their capacity over time, and they lose their capacity the more we tend to recharge them. If you’re finding that the laptop is not charging the battery all, it may be related to the charging subsystem and you may need to swap that out inside of your laptop hardware.

If you’re plugged into a wall adapter and you’re not getting any power on your laptop, you may want to check the voltages coming out of the wall adapter, and you might also want to look at the power that’s coming from your external power adapter. This is one of the times when a multimeter’s very useful to be able to show you the AC voltages coming from the wall, and the DC voltages coming from your power adapter. It may also be that your laptop is simply frozen our hung. Sometimes you can perform a hard reset of your laptop by holding down the power button for 10 seconds. Different manufacturers have different ways are performing this reset, so you want to check your documentation to see which applies for your particular laptop model.

If you’re connecting your laptop to an external LCD display or a projector, you want to be sure to use the function keys that will allow you to toggle the output to the external video connection on your laptop. This is usually a Function key that’s on your keyboard– you can see the Function key here– and F8 has a CRT/LCD option so that you can toggle between your internal LCD display and an external display that’s connected to the video adapter on your laptop. You can usually cycle through four different connections to this external monitor or display. There’s usually a computer-only connection that is only on your laptop device. If you use the Function key again, you might be able to duplicate that or mirror the connection to that external display. You might also be able to extend the display so that your internal LCD and the external monitor act as two different monitors for your particular laptop. Or you might want to turn off your LCD on the laptop completely, and only display the output on the external device.