Troubleshooting Mobile Devices – CompTIA A+ 220-1001 – 5.5


Our mobile phones and tables are complex computing devices that can also suffer complex problems. In this video, you’ll learn how to troubleshoot display problems, app issues, battery problems, and more.

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If you’re using your mobile device, and suddenly the screen goes completely black, and it doesn’t respond to any type of input, or you were using the mobile device earlier, and when you pick it up, it doesn’t respond at all or show anything on the screen, then you may need to provide a reset to regain control of that mobile device.

To perform a soft reset in iOS, you would hold down the power button until the power off message is displayed. You would slide the power off. And then after the phone has powered off, you would press the power button again to power it back on. If you’re not getting any response, and the screen is black, you may have to perform a hard reset. To perform that hard reset in iOS, you would hold down the power button and either the home or the volume button depending on the version of iPhone that you had. You hold all of that down for 10 seconds. And the phone should restart.

With Android devices, the reset process can vary depending on what type of Android device you have. You can commonly remove the battery and replace it on many of these devices to perform a hard reset. Other phones may provide a reset by holding down the power button and a volume button until the device restarts. But this can vary depending on the model of Android device that you have.

There may be instances on your mobile device where the apps are not performing as expected. They may not be loading at all, or the performance may be very slow. You may want to stop the app completely and then restart it to see if the problem continues. In iOS, you would either double tap the Home button or slide up from the bottom. And then slide the app up and off the screen to be able to close it. You can then restart the app from the main menu of the mobile device.

In Android, you can force stop an app by going to the Settings slash Apps option, selecting the app that you’d like to stop, and then choosing the force stop option. The app issue may be related to the overall performance of the phone. So resetting the phone with either a soft or a hard reset may be able to clear up any problems that might be occurring. You could also try to update the app if an update is available. The developer of the app may have identified problems with the application. And simply updating the application may resolve any of those issues.

Whenever we’re sending or receiving emails from these mobile devices, we’re almost always doing it over an encrypted channel to provide the highest level of security. But if you’re having problems decrypting this incoming email, then you may want to check some of the configuration settings for emails on your mobile device. If you’re in a corporate environment, you may be using a local or a cloud-based version of Microsoft Outlook.

In the case of Outlook, each individual user has their own private key. And information cannot be decrypted unless the private key is properly installed on that mobile device. Usually, you would have private keys installed from a central management station, such as a mobile device manager or an MDM. And the system administrator for all of your mobile devices can use this MDM to deploy those private keys to anyone who might be having a problem.

We rely on the batteries inside of our mobile devices to keep us connected when we may not be anywhere near a power source. And if your battery life tends to be shorter than what you’re expecting, there may be some things you can do to help resolve the problem.

If you have your phone in an area that has very bad reception to your mobile provider, you may find that your battery is going down faster than you would expect. That’s because this device is constantly searching for a signal and using the radio and therefore the battery to perform that function. This might be one of those situations where you enable airplane mode while you’re on the ground just to make sure you’re able to conserve battery while you’re away from that mobile network.

Other radios that are inside of this device are also using battery. So if you’re not using your 802.11 wireless, you’re not using your Bluetooth, and you’re not using GPS, you may want to disable those features as well. The manufacturers of these mobile devices also give you some insight into the battery use. On an iPhone, you can go to Settings, Battery. And on Android, you go to Settings, Battery, to be able to see how much battery is still remaining and get a breakdown of how much the battery has been used by applications.

Eventually though, you will have to replace the battery in these aging mobile devices. Those batteries only have a certain number of recharges that they can support. And after you reach a particular limit, you’ll need to replace the battery so that you can continue to use this mobile device over an extended period of time.

Our mobile devices continue to get smaller and smaller. And those components within the device continue to create more and more heat. If this heat becomes excessive, these devices will automatically power themselves off to protect those components. There are ways, though, that you can minimize the amount of heat that’s being created inside of these mobile devices.

For example, when you’re charging or discharging the battery, there is heat that is coming directly from that battery. If you’re using a lot of CPU, that will create heat inside the device as well. And using the display light and other components inside this device will all create heat.

You can also check the application usage and see how much of the battery is being used for each individual app. That might point you towards an app that is using an excessive amount of CPU. And by disabling that app, you may be able to reduce the temperature inside your mobile device. And of course, you should avoid putting your mobile device in direct sunlight or on the dashboard of your car. This will heat this device up very quickly. And you’ll find that it will power itself off in a matter of minutes.

I think we’ve all had the situation where our mobile device suddenly stops working. It freezes completely. You’re not able to get any response from the screen. Nothing is moving. Even the clock has stopped updating on the screen itself. If you can perform a soft reset where you’re simply holding down the power key, you may be able to power off the system and then restart it again.

But if your system’s not responding to a button press, you may have to perform a hard reset. On iOS, you would hold the power and either the home or the volume button for 10 seconds. On Android devices, it’s a similar set of keystrokes to be able to perform that hard reset. The hard reset should allow you to regain control of your mobile device. But if this is an ongoing problem, you may want to consider performing a factory reset and reloading your apps as if this was a brand new install.

If you’re not getting any sound from an application that’s running on your mobile device, you may want to check the application settings for volume and check the overall volume of your mobile device. It could be bad software. So simply deleting the app and reloading it might solve the problem.

You might also want to try using headphones to see if the problem is with the hardware of the phone or with the application. If the sound starts to play and then suddenly stops again, you may have different applications that are trying to control the audio output for your mobile device. You may want to try keeping one of those applications in the foreground to see if that sound continues to work properly.

If you’re getting no audio from your mobile device, you may want to try installing the latest version of your operating system to see if there happens to be a bug fix for that problem, or you may want to start fresh by performing a factory reset and then loading the latest software and your applications.

Our mobile devices include global positioning system or GPS hardware that allows our applications to know exactly where we happen to be. If this is not working properly, we may want to check the settings and make sure that the GPS is turned on. In iOS, you can look at Settings, Privacy, and Location Services. And on Android, you can look at Settings and Location.

You might also have options on how you’re using GPS and how it interoperates with other types of location services. You can turn on and off these different options from within the location mode settings in your mobile device. In iOS those are under Settings, Privacy, and Location Services. And on Android, those are under Settings, Location, and Location Mode. And of course, because these GPS signals are coming from satellites, we need a good view of the sky to be able to get an accurate representation of where we may be.

If you’ve managed mobile devices before, then you’ve probably run into one of these batteries that suddenly has blown up and looks like a pillow. This is a battery that’s failed and has a buildup of gas inside of that battery case. This is designed to self-contain all of that gas. And you need to be very careful not to puncture or have any damage to that container.

This battery may expand within the mobile device, causing the device to become damaged or to pop open like this one does. Make sure you stop using that device immediately. And you’ll want to dispose of that battery very, very carefully. Although it’s unfortunate that this expansion of gas inside the battery can damage our mobile devices, it’s preventing this device from catching on fire. So this is a very important safety feature in all of our mobile devices.