Galaxy S8 only turns on to Download Mode; won’t turn back on normally

We’ve noticed that many #GalaxyS8 users are now experiencing power troubles at this time so here’s another shot at how to fix a common power-issue scenario. In a lot of cases, power troubles usually end up with repair so hopefully, the case mentioned in this post will avoid that.

Problem #1: Galaxy S8 Bluetooth stopped working after screen replacement

Hi there. I have a Samsung Galaxy S8 G950F and recently cracked my back screen. I got it replaced by an approved repairer and was told my phone still retained its water resistance rating. Water however a couple weeks later got into my phone. At first the power and volume up buttons became non-responsive. During the day, the Bluetooth then turned off and could not switch on. The iris scanner failed and water could be seen fogging up the front and rear cameras, which however were still functioning despite poor quality due to the water. The ambient light sensor also failed and I had to manually toggle brightness. A day later and all physical buttons worked normal again and my Bluetooth turned on again so I could use it. I ran hardware tests through Samsung’s Members Application and it told me my light sensor, barometer and magnetic sensor needed a check. 3 days later the water cleared from my cameras and I restarted my phone – did not restart previously. Now the iris scanner is working normally, so is the barometer, cameras, buttons and test hardware shows all sensors working normally, except for Bluetooth. Been 3 days and a few restarts and the Bluetooth only now is not functioning. What wouldn’t you guys recommend I try other then to send my device in for a check, as I believe it could be back to normal? Thank you so much for the feedback guys! — Mohammed Mulla

Solution: Hi Mohammed. The moment your phone was taken apart by a technician during repair, its water-resistance protection was gone. This is a one-time protection and even a Samsung technician can’t make it water-resistant again. You were clearly misled into thinking that this was not so by the shop that serviced your device. Even if the shop did fix the screen properly, which we don’t think they did due to the fact that the soft buttons did malfunctioned after the screen replacement, water or moisture may still have damaged new components or the main logic board. Like other functionalities, Bluetooth requires a good hardware as well as working software. Since the rest of the initial malfunctions no longer bothers you for now, we recommend that you try a factory reset to ensure that your S8’s software is fresh. In factory state, we know for a fact that Bluetooth works so if the Bluetooth functionality is still down after a reset, you know for a fact that the cause of your problem is hardware-related. There’s no magic software tweak that you can do to fix a bad hardware. If we are right to say that your Bluetooth issue is due to bad hardware, the only way to fix it is to either have a motherboard replacement or a phone replacement.

For reference, here are the steps on how to factory reset your S8:

  1. Back up data on the internal memory. If you have signed into a Google account on the device, you have activated Anti-theft and will need your Google credentials to finish the Master reset.
  2. Turn off the device.
  3. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
  4. 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).
  5. Press the Volume down key several times to highlight “wipe data / factory reset.
  6. Press Power button to select.
  7. Press the Volume down key until ‘Yes — delete all user data’ is highlighted.
  8. Press Power button to select and start the master reset.
  9. When the master reset is complete, “Reboot system now” is highlighted.
  10. Press the Power key to restart the device.

Problem #2: Galaxy S8 only turns on to Download Mode; won’t turn back on normally

Hi! My name is Didson and I live in Sao Paulo, Brazil, but am writing from Curitiba, in another state of Brazil. I have read several posts on this site and I have to tell I wish to have searched for it earlier.

My phone is not even one year old, but it was presenting since a while ago the message warning the slow charging problem, and to connect the mobile to the original charging unit, even though I had it plugged in already. I never bothered to look deeper into this but yesterday I updated the Android to 8.0 Oreo, and today I noticed a battery drain much higher than before, even when the original charging adaptor connected, or the car charging adaptor, the phone just wasn’t charging.

I shut it down when it was with something about 4% battery, and left it connected to the mains with the original charging adaptor unattended. When I finally checked it again, it wasn’t showing the charging screen which normally shows even when phone is turned off… It was very hot though.

By now, I have already tried to turn it on by normally, in forced restart not plugged and plugged in the mains, safe mode and recovery mode. NONE had any effect to the phone! The only mode that I managed to enter after reading other blogs was the Download mode which shows a ODIN screen with stuff that I don’t understand, so I just left it by following the instructions (Volume down + power key for 7 seconds). I don’t know what is going on with my phone and I am not in my city, I really need it back fast! Thank you very much for the attention and future help. — Didson New Pereira

Solution: Hi Didson. We hope you’ll read this post in time but if you’re positive that your S8 still powers on albeit in Download or Odin Mode only, that can be an indicator that it’s having an issue loading Android. This means that your phone is not totally dead; it’s just unable to boot up normally, most probably due to bad bootloader or a corrupted operating system (Android). Given the circumstances you’re in, the only way to fix your problem may be to reflash the bootloader (this will address any possible issue with your phone’s Recovery software), or by flashing the firmware.

Flashing is an Android equivalent of “installing” the operating system or firmware. This is very risky procedure and won’t guarantee a solution. When flashing, you’re basically modifying sensitive system files and if you make a mistake, you might be causing more problems than the one you already have. This procedure also requires a computer and of course, some advanced knowledge about Android and how to fix it should something goes wrong. Needless to say, it’s only recommended for advanced users, those who knows how to find ways to fix should they encounter issues after tampering with the software. We don’t usually recommend flashing due to its risky nature but this can be your only way out.

If possible, try to let Samsung check your device so they can help if our assessment is correct. They have the tools to flash devices. If you can’t take your S8 to a Samsung store or service center, ask someone to help you flash the bootloader first. If that won’t work, try flashing the firmware as well. If both procedures won’t work, you’re out of luck; you may end up with an expensive paperweight.

Our blog does not provide flashing guides so try to visit those that do. We suggest that you engage Android communities in forums like XDA Developers forum website. There are many brilliant Android users and one of them may lead you to a flashing guide for your phone.