Troubleshooting Mobile Devices – CompTIA A+ 220-901 – 4.5

Troubleshooting a mobile device can be a challenge for the best technician. The combination of proprietary hardware, unique software, and a mobile platform requires a unique set of troubleshooting skills. In this video, you’ll learn how to resolve a number of issues that can occur on mobile devices.

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We all love our mobile devices, but sometimes they don’t operate the way we might expect. So, in this video, I’ll step you through some of the common troubleshooting tasks for our mobile devices. Sometimes our mobile device screens become completely unresponsive. Maybe the screen is black and, no matter what buttons we press or where we touch on the screen, it doesn’t seem to respond. This might indicate a problem with the hardware of the phone, but it could also be software related, so we might want to reset the phone itself.

In iOS, we can perform a standard reset by powering off the device by holding the Power button, sliding the message to say Power Off, and then pressing the Power button. This obviously is going to be a problem if the touch screen is unresponsive. We’re not able to slide to Power Off.

So what we may want to do is perform a hard reset. To do that, we hold down the Power button and the Home button at the same time. We hold them for 10 seconds. The phone will automatically power itself down and then power itself back up again by pushing the standard Power button.

On most Android devices, we can simply remove the battery to perform a hard reset. So we’ll remove it, put it back in, and then try powering on the phone again. There might also be a number of key presses that you can use to be able to reset the phone.

Sometimes it is a power down and a volume down until the phone restarts. Different phones are going to use different methods to be able to perform this hard reset. So check with your phone documentation to see what the process might be to be able to have this phone hard reset and restart the system.

We rely on these applications running on our mobile devices to perform productivity tasks or play games. Sometimes the app just is not responding the way we might expect. Maybe we tried loading the application, and it simply doesn’t load at all. Or maybe it runs slower than what we might be expecting.

What we might want to do is to restart the application itself. On iOS, we would double-tap the Home button. And that’ll bring up a list of all the applications that are currently in use. You can find the application and then slide it up to close it out of the memory. In Android, you can go to Settings and Apps, select the application, and choose Force stop.

Sometimes restarting or resetting the mobile device can free up the memory that’s causing this particular application not to work properly. Or maybe the application is outdated and needs an update. Try getting the latest version of the application and see if that solves the problem.

We rely on our mobile devices to keep our information private. And this certainly applies to our email messages. When we’re sending emails back and forth, we want to be sure not only are the emails stored privately on our mobile device, but the communication to our email server is also an encrypted channel. Sometimes this encryption method is built into the email application itself.

For example, Microsoft Outlook has built-in encryption methods to be able to not only store the information in encrypted form, but also send and communicate encrypted, as well. Different applications handle this encryption process in different ways, but one way that’s common across many applications is that each individual user will have their own private key. And it’s this private key that’s used to encrypt the data before you send it to a separate party. The administrator is generally going to make sure a private key is generated for every individual and then make sure that private key is installed on each mobile device. Usually the administrator has an MDM, or a Mobile Device Manager, that can help deploy these different keys out to the mobile devices.

One challenge we always have with our mobile devices is making sure we have enough battery life. And occasionally we may find that the battery seems to be depleting faster than we might expect. Sometimes this is caused because your phone is just outside the range of your wireless provider. So your phone is trying to reconnect to your wireless provider, not being able to connect, and then trying again. And this process of constantly using the radio inside of your mobile device is depleting your battery faster than what you might expect.

In these cases, you may want to completely disable your cellular communication and maybe rely just on the 802.11 or internal wireless network that might be in your home or office. There might also be some features of your phone that you can disable completely and, therefore, not use any battery. If you’re not using the 802.11 wireless, or the Bluetooth connections, or your GPS, you can sometimes disable each individual feature and save that much more battery life.

Most mobile devices allow you to see which applications are using the most memory. Maybe we have an application that’s constantly checking your location, or it’s constantly processing a certain amount of information. In iOS, we can look at this under Settings, General, and Usage. And, in Android, we can look under Settings and look at the Battery option.

If your phone is over a year old, you may find that it’s not holding the battery life the way it used to. Our batteries are only able to recharge a certain number of times, so you may find that a battery replacement will solve this particular problem.

Our phones and our mobile devices are remarkable computing platforms. But they are sensitive to heat. And, if we happen to leave our phone in the sun, you may find that it overheats and automatically turns itself off to prevent any damage to the components.

You can also create heat inside of your phone in other ways. You may constantly be charging and discharging the battery. There might be a lot of CPU usage for a particular application. Or maybe you have the light on, and it’s causing additional heat inside of that device. If it doesn’t seem that your phone is doing anything, and yet it’s still getting warm, it’s probably because an application is using a lot of CPU cycles. So check the application usage on your mobile device and see what applications may be using the most amount of battery or the most amount of CPU.

And one thing you want to be sure to avoid is any extended direct sunlight on the phone. This will heat up the phone very quickly. So make sure you don’t keep the phone on the dashboard of your car or out at the beach in direct sunlight.

Our mobile devices are complex combinations of hardware and software, but sometimes they do you run into a problem where the entire system will hang. When our systems are frozen in this way, they’re completely unresponsive. No matter what keys we press or what we do on the screen, it doesn’t seem to respond at all.

So the only option is going to be to restart the phone. You can try a soft reset by holding down the Power button. But if the system really is frozen, you may have to resort to a hard reset.

On iOS, we would hold down the Power key and the Home key for 10 seconds to perform a hard reset. On Android, it depends on the Android system you’re using. But it’s usually a combination of the Power, the Home, and the Volume buttons. If this problem continues to occur over, and over, and over again, then the issue may be with hardware, or it may be the operating system of the mobile device. One thing you can try before replacing the hardware is to perform a factory reset on the device and start the software from scratch, that way you can determine if it’s really associated with the software, or if you might have a hardware problem.

We use our mobile devices for so many different kinds of media that we’re constantly using the speakers and the audio features. Sometimes we have problems with applications not providing any sound at all. So you might want to check the volume settings. Not just the volume settings for the phone itself, but sometimes the application has its own set of volume settings.

You might also want to see if the software’s been installed properly. So you may want to delete the app and reinstall it to see if that fixes the audio issue. And you may want to see if the problem is with the external speakers or with the audio subsystem itself. So plugin some headphones and see if the problem also exists inside the headphones.

If an application starts playing some sound and then stops, you may have two applications that are trying to use the sound subsystems simultaneously. So you may want to see what other applications are running or leave one application in the foreground and see if the problem continues. If you’re not getting any sound at all from any application for anything on the mobile device, you may have a problem either with the software or the hardware of the device. One way to check for a software problem is to load the latest software applications or perform a factory reset and see if the problem continues.

We rely on the GPS and location features of our mobile devices not just for maps, but also to tell us what might be around us, or how long it might take us to get home. If you’re finding that the GPS capabilities are not working as expected, you may want to make sure that they’re turned on. On iOS, it’s under Settings, Privacy, and Location Services. And, under the Android operating system, it’s under Settings and Location.

There’s also a Location mode on your phone that might not specifically use GPS, but can also use other methods to determine where you might be. You can check that configuration in iOS under Settings, Privacy, and Location Services. And, under Android, it’s under Settings, Location, and Location mode. If you do want to take advantage of the GPS functionality, you need to be sure you have a clear view of the sky. You’re listening to the satellites that are surrounding you, and you want to be sure you’re able to hear the signals coming from many different satellites simultaneously.

A problem that I hope does not happen to you, but it certainly can be an issue on our mobile devices, is when we have a swollen battery. This is due to a fault inside of the battery itself that builds up some gas. But it’s designed to contain all of that within the battering enclosure. When that happens, the battery will bulge out, as you see here. And, unfortunately, it often creates problems for the device around the battery, as well.

You do not want to open this battery container. This has chemicals inside of it that could start a fire. You want to be sure that you don’t use any scissors or anything sharp around this battery container, and you want to stop using this device immediately.

You want to take this to a technician that knows how to dispose of these batteries properly and hopefully can solve any hardware problems that were caused by this battery expanding. Unfortunately, it’s very common for our devices to become damaged whenever these batteries expand. But this is certainly much better than having a fire or causing any type of chemical leak inside of your device.