Galaxy S8 And Galaxy S8 Plus Shuts OFF Randomly (Solution)

The most recent firmware updates of Samsung Galaxy S8 and Galaxy S8 Plus have generated a wave of complaints from the users of these devices. For the last couple of months, numerous persons reported that their phones have begun to randomly shut off, in the most unexpected moments. If you’re going through the same problem, however, you don’t necessarily have to blame the updates. It can also be a hardware problem, a malfunctioning battery, a physical damage that the phone suffered and you didn’t pay too much attention to, and so on.
On the other hand, if you can directly connect the moment when you performed an update to the moment when the random shut offs started to manifest, you are clearly dealing with firmware-related problems. Since we’re getting so many troubleshooting requests and questions from our readers, we decided to put together a comprehensive guide in this direction.
Our advice is to reach out for professional help from an authorized technician. That’s because even though the troubleshooting advice is generally safe and sound, there may still be instances when the situation can go from bad to worse. Consequently, if you’re trying to fix on your own the Galaxy S8 or Galaxy S8 Plus that turns off randomly, you are doing it at your own risk.
Now let us put this disclaimer behind and introduce you to the four most important things that you can check on your own.

Does it have to do with the battery?
One of the reasons why a smartphone will shut down suddenly is a malfunctioning battery. If the problem triggers even when you’re connected to a stable power source, it’s not the battery. But if it doesn’t, you can suspect that the battery has either been damaged or just lost its capacity to power your phone.
To see if it’s only a battery draining issue, connect the charger, let it sit like that for a couple of minutes, and then restart the Galaxy device. If you no longer experience such problems after that, you would have to go to a technician and ask for a battery replacement. You can order it online and pay for the replacement intervention or you can ask them to handle the entire process. Either way, you won’t be able to remove the battery on your own, so, eventually, you will end up in a service.

Does it have to do with a third-party app?
Practice has shown us that, sometimes, a faulty app can make your phone freeze or even shut off out of the blue. As you probably know by now, the best environment where you can test the third-party app issues and safely remove the faulty apps is the Safe Mode.

For this purpose, you will have to:

Boot your Samsung Galaxy S8 into Safe Mode;
Use it in the Safe Mode for as long as you can and determine if it still shuts off unexpectedly;
If it does, identify and uninstall the app;
If you can’t find the responsible app, back up your data and reset the device.

To boot into Safe Mode, just press and hold the Power button. When the text “Samsung Galaxy S8 ” appears on the display, release the button and tap on the Volume Down key. Press this second key until the phone reboots and only release it when you see the text “Safe Mode” on the display.
If the phone still shuts down when in Safe Mode, it is clearly not a third-party app. That’s because these apps won’t run in this mode, only a couple of pre-defined apps and services do. So, if it continues, you need to identify the faulty app and uninstall it. The alternative, as mentioned, is to simply back up all the important data and to initiate the reset as it follows:

Exit the Safe Mode;
Head back to the Home screen of your Galaxy S8 Plus;
Tap on the Apps icon;
Open the Settings section;
Hit Backup and Reset;
Select Factory Data Reset;
Tap on Reset Device;
Use your PIN or password when prompted (this one will most likely show up for those with an active screen lock feature on their devices);
Confirm by tapping on the Continue button;
Initiate the process by tapping on the Delete All button.

Does it have to do with the system cache?
This is probably not the most intuitive choice when you suspect that your problem started from a firmware update. But considering that an impressive number of Samsung Galaxy S8 and Galaxy S8 Plus devices have problems precisely because of the corrupt cache, it is mandatory that you verify this situation as well.
Basically, you will have to boot the phone into Recovery Mode and, once in there, to delete the system cache. The process is completely non-invasive and safe, without you risking to lose any kind of files or data, provided you stick to our instructions from below:

Turn off the device;
Press and hold, at the same time, the Home button, the Volume Up button and the Power button;
When you see the text “Samsung Galaxy S8 ” on your display, release the Power button;
When you see the Android logo on the screen, release the other two buttons;
Wait for up to 60 seconds and then you can start navigating within the Recovery Mode.
Highlight the Wipe Cache Partition feature with the Volume Down key;
Start the wipe cache with the Power button;
Use the same two buttons once again to highlight and initiate the option “Yes” on the next screen option;
Wait for the wipe cache partition process to end;
Use the two buttons, again, to highlight and initiate the option Reboot System Now;
Wait for the device to finish the reboot, which will take a bit longer than usually.

The ultimate solution is a Master Reset
When not even the wipe cache partition stopped your Galaxy S8 or Galaxy S8 Plus from randomly shutting off, looks like you will have to perform a master reset. Back up all your files from the internal storage, so you won’t remain without your important data when you start to delete everything. After that:

Turn off the smartphone;
Get the phone into Recovery Mode
While holding these two buttons, tap on the Power key as well – this is the moment when the command is taken into account, so do not worry that you’ve been holding the other two keys for too long;
When you see the text “Samsung Galaxy S8 Plus” on the display, let go of the Power button;
When you see the Android logo on the screen, release the other two buttons (you could also see the message Installing system update, in which case you will have to wait a little longer until the logo will show up on the display);
As you have entered the Recovery Mode, use the Volume Down key and select Wipe Data / Factory Reset;
Use the Power key to start the reset;
Use the Volume Down key to highlight the option asking you to confirm this action: “Yes – delete all user data”;
Use the Power key to officially launch the reset;
When the reset is done – which will take some time, highlight the Reboot System Now option;
Initiate it with the Power key and wait for the phone to reboot – again, it will take more than what you’re used to.

When all this is over, your Samsung Galaxy S8 or Galaxy S8 Plus will run in the normal functioning mode. By now, the random shut offs should have found a fix, but if it’s still happening, really, it’s time for you to take it to an authorized service. Those technicians will have all the necessary tools for troubleshooting even the most complicated hardware problems.