How to fix a Galaxy S8 with black screen issue after a factory reset

For those #GalaxyS8 owners having black screen issue, this one’s for you. We know that there’s a lot of S8 devices that suffers an unfortunate fate of having a black screen issue so our suggestions below might help some. The solutions below are not meant to fix all black screen issues (there are a lot variants for this problem) but generally, as long as the reason is not hardware malfunction, these suggestions should work:

  • cache partition wipe
  • safe mode
  • factory reset.

In many instances of black screen problems, the cause is physical damage. If your S8’s screen turned black or unresponsive after you dropped it or after it got wet, skip our suggestions and bring your phone to Samsung instead.

Problem #1: How to fix a Galaxy S8 with black screen issue after a factory reset

Black screen, but system is responsive. Volume, can swipe and select stuff (blindly), receive calls. Just can’t see. I would like to believe it is the LCD, except when rebooting, can see the static splash screen (Samsung Galaxy S8 in middle and Android at the bottom) and the dynamic Samsung logo. Then blackness. Tried factory reset, but didn’t help. If it weren’t for the boot up displays, I’d just replace the screen/digitizer. 

Solution: We don’t think there’s a problem with your S8’s screen. The fact that the Samsung logo screen comes up during a restart is a clear indicator that it’s working fine. The black screen issue you’re having must either be due to a bad third party app or corrupted operating system. To fix it, here’s what you can do:

Check if screen works on safe mode

Incompatible app or poorly coded app may interfere with Android operating system. To see if you’ve installed one that might cause this trouble, try booting the phone to safe mode. Here’s how you can do that:

To boot your S8 to safe mode:

  1. Turn the device off. This is important. You won’t be able to boot to safe mode if you can’t turn the phone off first.
  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 you are able to reboot your phone to safe mode, that means there’s an app causing the problem. To identify which of your apps is causing the trouble, you should boot the phone back to safe mode and follow these steps:

  1. Boot to safe mode.
  2. Check for the problem.
  3. Once you’ve confirmed that a third party app is to blame, you can start uninstalling apps individually. We suggest that you begin with the most recent ones you added.
  4. After you uninstall an app, restart the phone to normal mode and check for the problem.
  5. If your S9 is still problematic, repeat steps 1-4.

Get help from Samsung

If you are not able to restart your S8 to Safe mode at all, you can bring the device to Samsung so they can reflash its software. Depending on the status of your phone’s warranty, this may or may not be free.

Reflash stock firmware to your device

If you’ve already tried flashing a Samsung device before, doing the same on your current S8 may also help. We only recommend this solution for advanced Android users as it entails tampering with the software. There’s a big chance that you’ll end up causing more, severe software problems than solving the current one if you can’t flash the device correctly. Generally, flashing procedure is as simple as following instructions but it doesn’t mean nothing can go wrong. In fact, a lot can go wrong with flashing since there are a number of factors that might mess up with the procedure. If you haven’t heard of flashing before, or if you’re not confident to do it, then simply let a professional do it for you.

Flashing guides vary by phone models so be sure to do enough research if you intend to take the risks involved.

Problem #2: T-Mobile Galaxy S8 used on AT&T network keeps showing there’s an available update

This is a T-Mobile “unlocked” device that I am using on the At&t network.  I just purchased it last week, and have moved everything over and am comfortable with the new platform except for one thing…. It is ALWAYS ALWAYS ALWAYS telling me in my notification pull-down tray that T-Mobile update service has a software update available.  I have done this update manually, 2x now. The notification remains. I have also tried “schedule update” so that it automatically performs the update overnight between 2am and 5am. For the past 4 nights it has updated automatically. Still, after these updates, the phone is notifying me that there is an update available.  In addition to the message always being in my notification tray, a FULL SCREEN white banner pops up randomly throughout the day, interrupting my tasks, also urging me to perform this update, giving me the option to “update now” or “schedule for later”. THIS is by far the most annoying thing. I have gone into my notifications menu to seek to turn off these notifications.  I cannot find an option to do this. Not even under Advanced notification settings. It seems impossible to turn off system update notifications. And why, after obeying and performing the updates so many times, is it still telling me there are updates to the software? No way could there be new software released every 5 minutes day and night. On my old phone (Galaxy S4) I never was forced into constant updates.  In fact, I’d have to manually search for a software update, and then if one was available, I could choose to either update my phone or ignore the update indefinitely. It never pestered me. So I am very upset, and I’m not sure what to do. Is this because I’m using a T-mobile phone unlocked on the At&t network? Please give me some advice.

Solution: The only reason that we can think of concerning your issue is the fact that you have a carrier-branded device being used in another network. Keep in mind that an unlocked device does not mean its software has been changed. At most, only the network configuration has been modified to allow the device to be recognized and permitted to work in a third party network like AT&T. Your phone’s software is still largely that of its original brand, which is T-Mobile (AT&T devices have distinct Android version of their own). While such an arrangement usually works nowadays, using a different Android firmware (T-Mobile) in another network (AT&T) can sometimes cause bugs or incompatibility issues. Your phone’s software at this time may be detecting that there’s an available update for it but it can’t actually download the said update since it’s incompatible (for AT&T devices only). This must be the reason why the system keeps on showing the notification for updates all the time now.

Carrier-branded phones are usually designed to automatically seek for updates whenever they’re online but in order to prevent bricking themselves, there is also a mechanism added to it to prevent them from installing incompatible firmware versions. So, basically, your S8 at this time may be getting some data that there’s an available update but since the available version is incompatible, it can’t take it. This goes thru a loop and may only end if the phone can be updated properly. To do that, we suggest that you bring it to a Samsung Service Center and see if they can manually update the firmware. If not, you can do some research on how to flash the software yourself.

IMPORTANT: After an update, the unlock codes for your device may no longer work so you may have trouble using it with AT&T network. Make sure to talk to your carrier to see if there’s a way to unlock it again after flashing or updating.