How to fix your Samsung Galaxy S8 Plus that turned off and won’t turn back on [Troubleshooting Guide]

Power issues often occur when there’s a problem with the hardware of your phone but there are times when a firmware issue may also cause the phone to turn off and won’t turn back on. Then, there’s a possibility your phone suffered from physical or liquid damage, which is a bit extreme and may need technical attention from an authorized Samsung technician. The point is we really won’t know what the problem is if didn’t try to troubleshoot the problem.

So in this post, I will walk you through in troubleshooting your Samsung Galaxy S8 Plus that turned off on its own and won’t turn back on when you press the Power key. We will look into every possibility and rule them out one by one until we get to the point wherein we can easily determine what the problem really is. That way, we can try to formulate a solution that might fix the problem for good. So, if you’re one of the owners of this device and are currently bugged by a similar issue, continue reading as this post may be able to help you.

Now, before we go to troubleshooting, if you are currently experiencing a different problem, try to visit our troubleshooting page for we have already addressed some of the most common issues owners encountered with their device. Find issues that are similar to yours and feel free to use our solutions or troubleshooting guides. If they don’t work, however, and if you need further assistance, contact us by completing our Android issues questionnaire. All we need is information so we can help you. Don’t worry, it’s free.

Troubleshooting Galaxy S8 Plus that won’t turn back on

As an owner, you have to do what it takes to make your phone work again, however, there’s only so much you can do with your device that won’t turn on. Our troubleshooting will be centered of course, on how to make your phone turn on and boot up normally but at the end of the day if the problem still persists after everything is done, then you should bring your phone to the shop and let the tech handle the problem for you. Now, to begin our troubleshooting, go through each step below:


Step 1: Force restart your Galaxy S8+

Assuming the phone turned off on its own without apparent reason, there’s a chance it’s just a system crash or a minor glitch in the system. Without doing anything complicated, you may be able to fix it on your own by doing just the Forced Reboot procedure.

Just press and hold the Volume Down and Power keys together for 10 seconds. If your phone boots up normally, the problem is solved otherwise, you have to move on to the next step or try a different method.

Step 2: Try charging your phone

Aside from replenishing the battery, you’re also trying to know if the phone responds when connected to its charger because if not, there’s a chance it’s a hardware issue and if that’s the case, it’s often serious.

So, plug the AC adapter to the wall outlet that works and then connect the other end of the cable to your phone and the other to the charger. You may see the charging sign on the screen and the LED notification at the top of the screen may light up but with or without these signs, give your phone 10 minutes to charge. After which if it still not responding, do what you did in the first step while the device is plugged in.

It’s logical to assume at this moment that the phone crashed while it’s battery got completely drained. Doing the forced restart while it’s charging may bring it back to life. However, if the problem still persists after this, then move on to the next step.

Step 3: Try starting your phone up in Safe mode

There’s a chance that this problem is caused by one or some of the apps you installed but since we don’t know which of those apps is the culprit, we need to disable all of them at once to isolate the problem. You can only do so by running your phone up in Safe mode. The moment your phone successfully boots up in this environment, it already confirms our suspicion so the next thing you should do is find the app that’s causing the problem and uninstall it. Now, follow these steps to run your device in 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.

And this is how you uninstall apps from your Galaxy S8+…

  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 or tap 3 dots icon > Show system apps to display pre-installed apps.
  4. Tap the desired application.
  5. Tap Uninstall.
  6. Tap Uninstall again to confirm.

However, if your device doesn’t boot up in safe mode, then move on to the next step.

Step 4: Try booting your phone up in Recovery Mode

If all steps above failed to bring your phone back to life, the last thing you should try is this procedure. The Android system recovery menu is actually the fail-safe of almost all Android devices. So, even if your phone is currently suffering from a serious firmware problem, it may still be able to boot up in Recovery Mode so you should try it because if successful, you can do a couple of things that may get rid of the problem for good; you can wipe the cache partition and do master reset.

How to start your phone up in Recovery mode and wipe cache partition

  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 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 the Power key to select.
  6. Press the Volume down key to highlight “yes” and press the Power key to select.
  7. When the wipe cache partition is complete, “Reboot system now” is highlighted.
  8. Press the Power key to restart the device.

How to start your Galaxy S8+ in Recovery mode and do master reset

  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.

If your phone failed to boot up in recovery mode, then it’s time to bring it to a shop as it might be a problem with the hardware.

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