How to fix Samsung Galaxy S9 that keeps rebooting randomly (easy steps)

Frequent and random reboots are more often caused by some firmware-related issues unless of course there’s an issue with the hardware. But for a new phone like the Samsung Galaxy S9, it’s almost impossible to have hardware-related problems that may lead to reboot issues. After all, Samsung has already learn its lesson with the Galaxy Note 7.

In this post, I will share with you the solution that we’ve always been using to fix phones that keep on rebooting without apparent reason. This is not the first time we address this issue, in fact, we received quite a lot of similar complaints with the Galaxy S8, which is too different with the current flagship. So, if you own this great phone and are currently experiencing random reboots, continue reading as this post may help you one way or another.

Before going further, if you found this post because you were trying to find a solution to your problem, then try to visit our Galaxy S9 troubleshooting page as we’ve already addressed most of the commonly reported issues with the phone. We’ve already provided solutions to some of the problems reported by our readers so try to find issues that are similar with yours and use the solutions we suggested. If they don’t work for you and if you need further assistance, fill up our Android issues questionnaire and hit submit.

How to fix Galaxy S9 that reboots randomly


For a new phone to be acting like this, it’s either the problem is minor and can easily be fixed or it could be a manufacturing problem. We have to rule out the former so that you all have the reason to get it replaced. Go through the procedures below to try and fix this issue…

First solution: Force restart your Galaxy S9

For minor issues, a reboot is usually enough to fix them but since we don’t know the reason why your phone randomly reboots on its own, it’s best to resort to a more effective solution–Forced Restart.

If you’re familiar with the battery pull procedure we often do to phones with removable battery, then this is the equivalent of that and we can only use this to phones like the S9 with non-removable battery.

Press and hold the volume down and the power keys at the same time for 10 seconds or more. If the problem is temporary, then your phone should not reboot on its own after this but if it still does, then move on to the next procedure.

Second solution: Run phone in safe mode and uninstall problematic apps

Rebooting the phone in safe mode won’t fix the problem but you would know if the problem is caused by third-party app or not. For instance, if your Galaxy S9 works without a hitch in safe mode, then it means there’s an app or two that you installed from the Play Store that’s causing this problem. You need to find that app and uninstall it.

Here’s how you run your phone in safe mode:

  1. Turn the device off.
  2. Press and hold the Power key past the model name screen appearing on the 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. When Safe mode appears in the bottom left corner of the screen, release the Volume down key.

And this is how you uninstall an app from your phone…

  1. From the Home screen, swipe up on an empty spot to open the Apps tray.
  2. Tap Settings > Apps.
  3. Tap the desired application in the default list.
  4. To display preinstalled apps, tap Menu > Show system apps.
  5. Tap UNINSTALL > OK.

However, if the phone still reboots while in safe mode, then we have to do after the firmware as that might be where the issue lies.

Third solution: Wipe cache partition

This deletes the system caches created by your Galaxy S9. You need to do this because some of them might have been corrupted for some reason. Corrupt caches will always lead to performance issues like this. Here’s how you wipe the cache partition of your phone. Don’t worry, none of your files and data will be deleted:

  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 Android logo displays, release all three keys.
  4. An ‘Installing system update’ message will show for 30 – 60 seconds before the Android system recovery menu options appear.
  5. Press the Volume down key several times to highlight wipe cache partition.
  6. Press Power key to select.
  7. Press the Volume down key to highlight yes, them and press the Power key to select.
  8. When the wipe cache partition is complete, Reboot system now is highlighted.
  9. Press the Power key to restart the device.

After this and the problem still continues, the next thing you have to do is a reset.

Last resort: Perform the Master Reset

At this point, a reset is already necessary. It fixes almost all firmware issues and some minor hardware problems so it’s worth it. Aside from that, it also prepares your phone for possible trip to the store as it deletes all your personal files, data and information. Make a backup of things you don’t want to lose and then disable the Factory Reset Protection by removing your google account from your phone. Once everything is set and ready, follow these steps to reset your device:

  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.

I hope that this troubleshooting guide can help you fix your Galaxy S9 that keeps on rebooting by itself. If you have other concerns you want to share with us, feel free to contact us or leave a comment below.

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