How to fix Samsung Galaxy S8 Plus that keeps randomly rebooting on its own [troubleshooting guide]

Does your #GalaxyS8Plus restart on its own lately? Today’s troubleshooting article will address this issue. You have to remember that this type of problem can be caused by different factors. We discuss what these factors are and how you’re going to handle them.

What causes random restart issue on your Galaxy S8 Plus

There’s a number of reasons why your Galaxy S8 Plus may be restarting by itself. These factors can vary in each of the case but so far, these are the common ones that we usually encounter:

  • Rogue app/s
  • Low/insufficient RAM
  • overheating
  • Inefficient app or Android coding
  • Unknown software bug
  • Bad battery
  • Water damage, exposure to cold
  • Hardware damage or malfunction

In order to effectively isolate which of these items is causing your issue, you need to know the history of the device and perform troubleshooting steps. Knowing your device’s history is a critical step because it can save you time, effort, and avoid the hassles of doing drastic but unnecessary solutions such as factory reset or repair. For example, if your S8 Plus had been working fine for weeks and the issue suddenly occurred coincidentally after installing your, say, favorite new game, it’s possible that said app may be to blame. Uninstalling it may save you time and effort instead of going through the rest of the troubleshooting steps in this guide. If your S8 only became problematic after you accidentally dropped it, there’s high likelihood that you may have damaged some components. In this case, it’s probably better to simply skip the software troubleshooting and go directly to sending the device in to Samsung.

If you can’t seem to know where the issue comes from though, you can start following the set of troubleshooting steps we provide below.

Force restart

Before you start doing any drastic solution options, keep in mind that some bugs, including some cases of random restart cases, are fixed by simply doing a force restart or soft reset. On devices with removable battery packs, this is done by disconnecting the battery from the device itself. However, in your case, you can only do its virtual equivalent by doing these steps:

  1. Press and hold the volume down button and don’t release it.
  2. Then, press and hold the power key while holding down the volume button.
  3. Keep both keys held down for 10 seconds or more.

Afterwards, observe your phone and see if the issue goes away. If it still remains, then go ahead and create a copy of your files, and follow the rest of the troubleshooting guide.

Create a backup of your personal data

Making a backup of your files should be your next priority in this case. It’s an imporant step to prevent data loss. This guide will touch on a number of possible causes and solution and one of them will ask you to wipe the device clean. While you still can, be sure keep your data intact in another device, or to a cloud service.

We won’t know how often your S8 Plus will restart by itself, or how much time you have between reboots but regardless, make sure that you don’t skip this suggestion.

In creating your backup, try to use Samsung’s official backup tool called Smart Switch. It’s an excellent tool if you want to keep virtually everything on your phone. If you don’t want to keep your backup in a computer, you can opt to save them in the cloud. Samsung does offer a limited GBs of free cloud services so try that first. Alternatively, you can use third party cloud services like Dropbox, Microsoft’s OneDrive, or Google’s own cloud service.

Clear cache partition

Now that you’ve already created a copy of your personal files, the first step to resolution is to ensure that you clear the cache partition. This is where Android keeps the system cache that is uses to load apps quickly. At times, installing updates or apps may corrupt this cache. By clearing the cache partition, you are basically deleting the system cache. Don’t worry, this cache will be rebuilt by the system over time so there’s no need to worry about losing anything.

To clear the cache partition on your S8 Plus:

  1. Turn off the device.
  2. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
  3. When the green Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds before showing the Android system recovery menu options).
  4. Press the Volume down key several times to highlight ‘wipe cache partition’.
  5. Press Power button to select.
  6. Press the Volume down key until ‘yes’ is highlighted and press the Power button.
  7. When the wipe cache partition is complete, “Reboot system now” is highlighted.
  8. Press the Power key to restart the device.

Observe in Safe mode

Sometimes, rogue, malicious, or incompatible apps may be added into a system. This usually occurs if a user is not mindful of what apps to install and from where they are coming from. If you’re adventurous when it comes to apps, there may come a time that you’ll encounter problems from one of them. To check if one of your apps is indeed behind the trouble, you need to restart your S8 Plus to safe mode and observe. Safe mode only allows pre-installed apps so if your device works normally and won’t restart on its own, that’s a clear yes to our suspicion.

To restart your S8 to safe mode:

  1. Turn the device off.
  2. Press and hold the Power key past the model name screen.
  3. When “SAMSUNG” appears on the screen, release the Power key.
  4. Immediately after releasing the Power key, press and hold the Volume down key.
  5. Continue to hold the Volume down key until the device finishes restarting.
  6. Safe mode will display in the bottom left corner of the screen.
  7. Release the Volume down key when you see Safe Mode.

If the problem seems fixed while in this mode, the next thing you should do is find the app that’s causing the problem and uninstall it. However, if the problem still manifests while in this mode, then try doing the next step.

Force quit all apps

If your device seems to restart only in random, without any discernible pattern to it at all, it’s probably just running out of RAM. Android is supposed to manage memory on its own but  there are some cases when this mechanism fails. You may need to intervene in these instances to help the system. There are two ways to do this. The first one is to close all apps by pressing the Recent button, the one on the left side of the Bixby key, and then tapping on CLOSE ALL button.

The other method is by doing these steps:

  1. Open Settings app.
  2. Tap Device maintenance.
  3. Tap Memory.
  4. Tap CLEAN NOW button.

We suggest that you do both methods.

Install app and Android updates

Sometimes, the most effective solutions are the simplest. In your case, the most effective way to fix the problem may be to simply install updates. Incompatible apps and outdated Android version may potentially lead to problems. To minimize that situation from happening, always ensure that you everything is up-to-date. This means installing updates for both apps and Android. If you have apps from non-Play Store sources, be sure that they are compatible with the current Android version you have.

Overheating

if you noticed that your S8 Plus becomes uncomfortably warm after using it for some time, it may be overheating. Be design, your S8 device is supposed to shut itself down when its core temperature reaches a certain limit. This is to ensure that the hardware is not damaged further by sustained heat buildup. So, if your S8 tend to heat up first before turning itself off, the hardware must be overheating for some reason. Oftentimes, this signals a hardware malfunction in the making but it can also very well be due to a software bug. make sure to continue the rest of the software troubleshooting below so you’ll know whether or not you have a software- or a hardware-related problem.

Check for water damage

The presence of water or liquid in the charging port can sometimes complicate things for devices like the S8 and S8 Plus, which have water resistance protection. In some cases, overconfident owners may decide to test out the limits of their phones by intentionally dunking their device in water. If you’re one of them, there’s a chance that your phone may have been water damaged. Your S8’s water resistance protection is not perfect so if there’s enough pressure applied to the charging port or to the sides, water may be able to penetrate weak spots. Water and electronics obviously don’t mix very well so if your s8 started acting up after getting it wet, you may have a possible hardware malfunction. To check for water damage:

  1. Look into the USB port to find any traces of moisture.
  2. Regardless whether there’s moisture in there or not, it’s better that you clean it up to get rid of any foreign materials that may cause more complications.
  3. Use a cotton swab to clean around the area or insert a piece of tissue paper to absorb the moist.
  4. Now check the Liquid Damage Indicator (LDI) to know if it’s tripped or not.
  5. Remove the SIM card tray and look into the SIM slot.
  6. If the LDI is still white, your phone is free of liquid damage but if it turned red or purple, it’s positive that water or any sort of liquid found its way into your device.

If you suspect that water may have gotten inside the phone, turn off the phone and send the device to Samsung for repair. Keep in mind that water damage is not covered under their warranty terms so even if the device is still within the warranty period, you’ll still probably end up with a hefty repair bill afterwards.

Reset all settings

Some users were able to fix random restart problems by resetting the device’s settings. This option has a similar effect to factory reset, without the hassle of deleting your personal data.

To reset the settings on your S8 Plus:

  1. Open Settings app.
  2. Tap General management.
  3. Tap Reset.
  4. Tap Reset settings.
  5. Tap RESET SETTINGS button.
  6. Restart your S8 and check for the problem.

Factory reset

To check for the possibility that there may be an unknown software bug causing your problem, you can do a factory reset. We know that factory state software does not have this issue so we hope that factory reset will help.

To factory reset your S8:

  1. Turn off the device.
  2. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
  3. When the green Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds before showing the Android system recovery menu options).
  4. Press the Volume down key several times to highlight ‘wipe data / factory reset’.
  5. Press Power button to select.
  6. Press the Volume down key until ‘Yes — delete all user data’ is highlighted.
  7. Press Power button to select and start the master reset.
  8. When the master reset is complete, ‘Reboot system now’ is highlighted.
  9. Press the Power key to restart the device.

Contact Samsung support

If all the software solution options won’t help solve the problem, that’s an obvious sign that you have a possible hardware issue. The common hardware failures that lead to a phone to randomly restart includes a bad battery, a damaged power management IC, broken charging port, or a general malfunction of the logic board. To fix your issue, be sure to seek professional help from Samsung.