How to fix Galaxy S7 random restarts issue, other issues

Random restart problem can happen due to a lot of causes. Today, we address this issue as we’ve received a number of #GalaxyS7 users reporting it. We hope you’ll get something out of this material.

If you are looking for solutions to your own #Android issue, you can contact us by using the link provided at the bottom of this page.

When describing your issue, please be as detailed as possible so we can easily pinpoint a relevant solution. If you can, kindly include the exact error messages you are getting to give us an idea where to start. If you have already tried some troubleshooting steps before emailing us, make sure to mention them so we can skip them in our answers.

Below are specific topics we’re bringing for you today:

Problem 1: How to fix Galaxy S7 random restarts issue, restarts on its own when using KnowRoaming SIM abroad

Samsung Galaxy S7 restarts over and over again ONLY when I’m overseas. I’m a flying crew and it happened twice in the span of 20 days. Once when I’m on the plane and once when I was in Jakarta. I tried several solutions but whenever I tried to connect myself to the internet (via WIFI or 4G), the phone just goes into an infinity loop (And at this point my keypad will be unusable for some reason). However when I arrive in my home country, my phone would miraculously be alright again. Note: I’m using a global SIM card called KnowRoaming whenever I’m overseas. — Aiden

Solution: Hi Aiden. Unlike other Android issues, it’s difficult to know what exactly is causing your problem since there’s a long list of possible reasons for it. A good thing to start doing first though is to check if the problem is being caused by the KnowRoaming SIM card. If your phone works normally fine when you’re back in your home country (and presumably using your local carrier’s SIM), it’s very likely that the KnowRoaming SIM card is interfering with the operating system causing it to behave erratically. You’ll most probably spending more effort in knowing this but we are almost positive that it has something to do with your third party SIM. otherwise, you can check the generic troubleshooting steps for standard random reboot issue below.

Install app and Android updates

Updates can contain fixes for known bugs so before you fly out again, be sure that your phone installs all available apps and Android updates. To check if your S7 has pending Android updates:

Launch Settings app.
Tap Software update.
Tap Download updates manually to make the phone search for latest updates. We suggest that you enable Download updates automatically option so let your device receive updates on its own.

Poorly coded third party apps can also affect other apps so in order to minimize problems from them, make sure that they run their latest available versions. Updated apps tend to have fewer issues than outdated ones.

Uninstall or disable apps

The more apps are running at the same time, the more memory (RAM) is being used up. In older devices, the lesser RAM there is, the more that a device tends to become problematic. Some may crash, while others may slow down in terms of general performance. We haven’t noticed these RAM issues in Galaxy S7 devices running Marshmallow and Nougat though. Android is designed to manage RAM on-the-fly by automatically closing some apps if necesarry to free up RAM, but it wouldn’t hurt if you’ll help close some yourself. To do that, simply tap the Recent Apps button (the button at the left side of the Home button) and tap X on the app you want to close.

Better still, you can uninstall or disable apps you don’t regularly use. Remember, the less apps you have in the device, the fewer the chances of bugs from developing. Remove apps you haven’t used in a few weeks, or those new ones you may have installed prior to noticing the problem. One of them may be causing the issue.

Restart the device to safe mode

If you suspect that one of the downloaded apps is to blame, try restarting your phone to safe mode and observe it for a few hours or even days. Safe mode blocks third party apps and services so it’s a good way to confirm your suspicion. If you don’t depend much of your daily activity on third party apps, try to extend the observation as long as possible to see a difference.

Basic phone functions like SMS/MMS, voice calling, wifi, mobile data and all pre-installed apps should still work so you can still use them while your S7 is in this mode.

Here’s how to restart to safe mode:

Turn your Galaxy S7 off.
Press and hold the Power button.
Once the ‘Samsung Galaxy S7’ logo appears, release the Power key and immediately press and hold the Volume Down button.
Continue holding the button until the phone finishes rebooting.
Once you see the text “Safe mode” at the bottom left corner of the screen, release the Volume Down button.

Ensure that phone has enough available storage space

Some Android phones can start encountering problems when there’s not enough storage space. As a rule of thumb, always make sure that your phone has more than 10% of total storage space as free to allow apps and the operating system to operate their caches without problems. We understand the Galaxy S7 has a limited internal device storage so try to keep non-system critical data and apps stored in the SD card. Photos, videos, music, and documents are better kept in the SD card to leave the device memory with plenty of space.

Reset the device to their software defaults

One important but drastic troubleshooting that you should do is factory reset. This will return all software settings to their known working state. There may be a process or service that causes the device to reboot on its own. Doing a factory reset should effectively address that problem.

Before you perform a factory reset, make sure to back your files up.

Turn off your Samsung Galaxy S7.
Press and then hold the Home and Volume UP keys, then press and hold the Power key.
When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
Using the Volume Down key, navigate through the options and highlight ‘wipe data / factory reset.’
Once highlighted, you may press the Power key to select it.
Now highlight the option ‘Yes — delete all user data’ using the Volume Down key and press the Power button to select it.
Wait until your phone is finished doing the Master Reset. Once completed, highlight ‘Reboot system now’ and press the Power key.
The phone will now reboot longer than usual.

Problem 2: Galaxy S7 crashed, showed black screen, won’t turn on at all

For a while, my S7 was boot looping but after a while, it would stop and let me actually use the phone. Lately however, the phone has frozen on a black screen with the blue notification light. After multiple battery drains and me trying to reset it, while failing due to freezes or crashes, my phone is completely dead. The phone looks like it’s turned off with just a black screen, and I’ve tried plugging it into a charger, so that it could charge. Before i would see the charging bar, even though it wouldn’t increase. Now all it shows nothing, and after an hour of being plugged into the wall, it’s cool to the touch. I’ve never missed with the firmware of the phone, other than updates. Any ideas on what to do? Thanks. — Harish

Solution: Hi Harish. We covered a similar issue for an S8 user a few days ago so kindly check this link. The device mentioned in that article is an S8 but the troubleshooting steps can all be applied to your S7 as well. Just remember, software troubleshooting can only address issues caused by a software glitch. If, for example, the main reason why the phone has died is a faulty battery, or motherboard error, there’s no amount of software tweaks that you can do to fix it.

Problem 3: Galaxy S7 keeps freezing and crashing after an update

I just purchased the phone yesterday and not long after getting home, it began freezing and randomly rebooting. The system had just updated, so I assumed it was just struggling a bit (like my S3 and S6 used to). It usually worked itself out on previous devices after a reboot or two. It hasn’t stopped though, I have no idea how to pin point what “seems” to trigger the freeze, I haven’t been able to do much with it since. I attempted a few different tests to troubleshoot from info here on your site, but have had no luck. Factory reset has been achieved, phone still shuts off in safe mode, and Sprint yet to be of any assistance… so i thought i would try my luck else where. No data has been transferred, and no damage to the device. — Miki

Solution: Hi Miki. There’s no common reason why a new phone would fail to turn on or keeps on restarting after an update. There must be an unknown cause why it does not work as expected after an update. Keep in mind that we’re assuming you have a brand new phone here and you were just doing an official over-the-air update. (If you tried to manually install an update via flashing, that’s a totally different issue and you should consider reflashing the previous working version). Since factory reset did not do any difference at all, you should consider returning the device to retailer so it can be replaced.

If you feel confident you can manage to try a software troubleshooting before returning the merchandise, you can attempt to reflash the bootloader. Below are the general steps on how to do that. Exact steps may be a bit different in some respects for your particular phone model so be sure to consult other guides.

Look for the correct firmware for your phone model and download it. Make sure that you select the right one. It should be the same exact firmware that ran previously on your device. We assume that you list down the firmware version somewhere. If you did not take note of it before, there’s a chance that you may pick the wrong one. As you may know now, using an incorrect firmware can cause complications so good luck with that.
Let’s now say that you have identified the correct firmware. You then want to download it to your computer. The firmware file should have a bunch of files in it like AP_, BL_, CSC_, etc.
Look for the file that starts with a label BL; this should be the corresponding bootloader file for this firmware. Once you’ve identified the bootloader file, copy it to your computer’s desktop or to any other folder that you can easily access.
Proceed with the rest of the flashing procedure using the Odin program.
In Odin, click on the BL tab and make sure to use the bootloader file you’ve identified earlier.
Now, make sure that the “Device Added” status and its “ID:COM box” has turned blue before hitting the START button. This will initiate the flashing of your phone’s bootloader.
Restart the phone once the procedure is finished.