S21 crashing/rebooting 1-2 times/day. Any tips on troubleshooting?

[dougleto]

I have as SM-G991U (256 GB S21 US version, stock everything but using Nova Launcher) that is randomly freezing/crashing then rebooting on me 1-2 times/day. Does android have any kind of crash log I could look at to try and figure out what's causing the problem? On the samsung forums, their support reps suggest running in Safe Mode, which I have, but it's not very useful because I can't reproduce the problem on demand and it usually happens 1-2/day, but sometimes less, so unless I just ran in safe mode all the time, that wouldn't tell me much. Plus, it would only tell me it's an issue caused by one of a hundred or so apps which, again, is not helpful.

So I'm hoping there is a crash log or something somewhere because I have no idea what triggers the crashes. The other night, it was sitting on a wireless charger, the screen wasn't on, then all the sudden it rebooted. It's not specific to any app or anything I'm doing. If there are no crash logs (which would be frustrating and disappointing), any other troubleshooting ideas are welcome!

 

[blackhawk]

Look for a memory leak. Typically a poorly written 3rd party apk.
Try clearing system cache.
Make sure auto restart isn't enabled...

 

[MAX 404]

I have as SM-G991U (256 GB S21 US version, stock everything but using Nova Launcher) that is randomly freezing/crashing then rebooting on me 1-2 times/day. Does android have any kind of crash log I could look at to try and figure out what's causing the problem? On the samsung forums, their support reps suggest running in Safe Mode, which I have, but it's not very useful because I can't reproduce the problem on demand and it usually happens 1-2/day, but sometimes less, so unless I just ran in safe mode all the time, that wouldn't tell me much. Plus, it would only tell me it's an issue caused by one of a hundred or so apps which, again, is not helpful.

So I'm hoping there is a crash log or something somewhere because I have no idea what triggers the crashes. The other night, it was sitting on a wireless charger, the screen wasn't on, then all the sudden it rebooted. It's not specific to any app or anything I'm doing. If there are no crash logs (which would be frustrating and disappointing), any other troubleshooting ideas are welcome!

Hi mate

For logs info check here and here

You can always flash firmware , using home_csc , to avoid factory reset the phone , if the problem is system related it will help

If is app related
Try booting in safe mode to see if problem goes away...

 

[dougleto]

Hi mate

For logs info check here and here

You can always flash firmware , using home_csc , to avoid factory reset the phone , if the problem is system related it will help

If is app related
Try booting in safe mode to see if problem goes away...

Thanks! I'll definitely try these out. I tried safe mode, the trouble is it's not really great as a diagnostic because the phone will go from 4-24 hrs between resets during normal operation, and since a phone in safe mode isn't terribly useful, it's hard to keep it in safe mode for long enough to see if that fixed the issue, if that makes sense. And then, if it did fix the issue, it just narrows it down to 1 out of a hundred apps! But maybe I'm missing something. Is there additional information I can find if I run in safe mode that would help suss out the problem?

 

[dougleto]

Look for a memory leak. Typically a poorly written 3rd party apk.
Try clearing system cache.
Make sure auto restart isn't enabled...

Thanks! I know how to clear cache but not how to check for memory leaks. Do you have a tool you'd recommend to do that? And I had never heard of auto restart before, so thanks for that. I confirmed that it is NOT enabled (that would have been a face palm moment!).

 

[MAX 404]

Thanks! I'll definitely try these out. I tried safe mode, the trouble is it's not really great as a diagnostic because the phone will go from 4-24 hrs between resets during normal operation, and since a phone in safe mode isn't terribly useful, it's hard to keep it in safe mode for long enough to see if that fixed the issue, if that makes sense. And then, if it did fix the issue, it just narrows it down to 1 out of a hundred apps! But maybe I'm missing something. Is there additional information I can find if I run in safe mode that would help suss out the problem?

Is not easy , you just need to be methodic

See if you can find anything useful in the logs first

Reflash firmware , use home-csc , see if it help

Have you notice if the phone fails under any specific circumstances?

If that does not help and if you can really relate the problem with any specific app you may try to freeze or uninstall suspicious app and let it run for a day , Package disabler app is a good option , it is easy to enable or disable app but is not free, you could try this one , is a debloater tool , it allow you to disable app... may be easy that having to uninstall / install by hand

 

[GillBates21]

I'm also having the same problem. Had the phone since June, it didn't start to occur until late August, which leads me to suspect it is an update related issue.

 

[dougleto]

I'm also having the same problem. Had the phone since June, it didn't start to occur until late August, which leads me to suspect it is an update related issue.

I'm glad you posted today, I've been meaning to post again here because I tried troubleshooting and am still having issues. In fact, it crashed twice today when I was trying to send a text message.

I installed one of the log applications (can't remember which one at the moment) but it wasn't really helpful. They didn't seem to catch any information related to a crash even though they were logging data at least twice when it crashed.

Then I tried reflashing using home-csc using ODIN and that ended up soft-bricking my phone (and yes, I followed all the instructions and used home-csc) so I had to reflash everything and do a full factory reset. That seemed to help, reducing the crashes from once/day to once/2-3 days for a few weeks, but now it's back to ~once a day (sometimes more, sometimes less).

So if anyone has any other idea, I'm all ears. When I was reflashing and stuff, I noticed in the recovery mode (or whatever it's called) options that you can look at logs. Does anyone know if one of those logs would have crash-related data or any other ideas of what to try? This is incredibly frustrating, especially that it's persisting after a factory reset. Argh!

 

[GillBates21]

I'm glad you posted today, I've been meaning to post again here because I tried troubleshooting and am still having issues. In fact, it crashed twice today when I was trying to send a text message.

I installed one of the log applications (can't remember which one at the moment) but it wasn't really helpful. They didn't seem to catch any information related to a crash even though they were logging data at least twice when it crashed.

Then I tried reflashing using home-csc using ODIN and that ended up soft-bricking my phone (and yes, I followed all the instructions and used home-csc) so I had to reflash everything and do a full factory reset. That seemed to help, reducing the crashes from once/day to once/2-3 days for a few weeks, but now it's back to ~once a day (sometimes more, sometimes less).

So if anyone has any other idea, I'm all ears. When I was reflashing and stuff, I noticed in the recovery mode (or whatever it's called) options that you can look at logs. Does anyone know if one of those logs would have crash-related data or any other ideas of what to try? This is incredibly frustrating, especially that it's persisting after a factory reset. Argh!

So what I tried to do is roll back all the default google app updates. Ex: Android system webview, Google app itself, etc etc. I factory reset it without backing up any apps (but pictures and messages etc), It was working for a few days and then it happened again. Which further reinforces my thinking that my problem is software based.

 

[dougleto]

So what I tried to do is roll back all the default google app updates. Ex: Android system webview, Google app itself, etc etc. I factory reset it without backing up any apps (but pictures and messages etc), It was working for a few days and then it happened again. Which further reinforces my thinking that my problem is software based.

So I'm curious why you think that means it's a software issue. If this isn't a widespread issue with the S21 and after we've both done a factory reset and still have the issue, that makes me think it could be a hardware issue. Of course, there could be some software incompatibility with an app that most people don't have installed or a bluetooth connection or something, which is why I really want to find a useful crash log (and find it rather absurb how hard it is to find a useful crash log on android, come on guys, it's a mature OS, some kind of crash log seems pretty basic!), because otherwise, it could be a ton of issues and I can't reproduce it. Ugh.

 

[GillBates21]

The reason is that the "few days" after the reset and restoring pictures, messages (but not apps) from backup, where there were no crashes at all (where previously it would happen at least 2 times per day).

 

[dougleto]

The reason is that the "few days" after the reset and restoring pictures, messages (but not apps) from backup, where there were no crashes at all (where previously it would happen at least 2 times per day).

Got it, that makes sense. I'm on t-mobile and just got an update this morning. We'll see if that improves anything because my device restarted 4 times yesterday

 

[GillBates21]

I havent had a crash like this since i disabled chrome and other google stuff, and downgrading google apps lol.

 

[dougleto]

I havent had a crash like this since i disabled chrome and other google stuff, and downgrading google apps lol.

How did you disable chrome and what other google stuff did you disable? (There's obviously quite a lot of google services that can't be disabled)

After the most recent monthly update, my phone has gone from rebooting multiple times/day to once every 2-3 days, which is more manageable but still super annoying. It is incredibly frustrating to me that there are no good tools to troubleshoot a crash (at least that I've ben able to find). Honestly, it's driven me to consider an iPhone for the first time in my life .

 

[GillBates21]

My trouble is back... I will be scheduling a fix with samsung soon so I can RMA it

 

[sandystays]

Check the below link. This seems to be a hardware problem which got solved after Samsung replaced the motherboard.
Samsung Restart problem

 

[isiddiqi]

So I bought this phone for my wife. Since I received the phone, after a day the phone started crashing whatever app she was on and then take you back to lock screen without having to go through a full restart process but it was definitely a restart as you would need to enter your pin again as opposed to fingerprints.

Since it was within 15 days of purchase I returned and reordered another one from Samsung, and to my surprise exact same issue. What are the odds of having two brand new phones having exact same issues.

This leads me to believe it must be a software issue. I just received this 2nd new phone last Friday.

 

[dougleto]

Yeah, I think what I was experiencing was a hardware issue (it definitely went through the full restart process, not what is described in the previous post). And from the link posted by sandystays above, it looks pretty common. I contacted Samsung support and was not impressed at all. They walked me through a number of troubleshooting steps that weren't helpful then had me take my phone to UBreakIFix. I did, they ran a diagnostic and their tools couldn't find anything wrong so they said Samsung should replace it.

Contacted Samsung, told them I had taken it in. They said I needed to take it to a technician (again, right after telling them I just had). They then said, oh, you'll have to mail it to us and you'll get your phone back in 7-10 business days. Their suggestion for what to do for a phone in the meantime? Buy a prepaid phone then return it when I get my phone back (which a) is unethical and b) wouldn't work anyways since they're locked). Ridiculous. They also admitted that this is a very common problem, so I asked why they just won't send me a replacement device if it's so common to which they had no real answer, just "that's our policy".

Eventually, I contacted T-mobile (my carrier) and was very pleasantly surprised. After me telling them the issue and the steps I'd taken to troubleshoot it, they sent me a replacement phone (recertified, but still) that arrived in 2 days. WAAAYYYY better than Samsung. The entire process made me a bit jealous of my wife's iPhone. If she had had a similar issue, we could have taken it to an apple store and not had the whole "our policy is that you have no phone for 7-10 business days" nonsense from Samsung AND the backup and restore process is still way better on iPhones than on any android I've ever owned. How there is no easy and reliable backup/restore mechanism on android after so long is beyond me.

Bottome line: if you have a similar issue, it's very likely a hardware problem (my replacement phone has been fine for 3 days now). And avoid Samsung support if you can!

 

[isiddiqi]

Yeah, I think what I was experiencing was a hardware issue (it definitely went through the full restart process, not what is described in the previous post). And from the link posted by sandystays above, it looks pretty common. I contacted Samsung support and was not impressed at all. They walked me through a number of troubleshooting steps that weren't helpful then had me take my phone to UBreakIFix. I did, they ran a diagnostic and their tools couldn't find anything wrong so they said Samsung should replace it.

Contacted Samsung, told them I had taken it in. They said I needed to take it to a technician (again, right after telling them I just had). They then said, oh, you'll have to mail it to us and you'll get your phone back in 7-10 business days. Their suggestion for what to do for a phone in the meantime? Buy a prepaid phone then return it when I get my phone back (which a) is unethical and b) wouldn't work anyways since they're locked). Ridiculous. They also admitted that this is a very common problem, so I asked why they just won't send me a replacement device if it's so common to which they had no real answer, just "that's our policy".

Eventually, I contacted T-mobile (my carrier) and was very pleasantly surprised. After me telling them the issue and the steps I'd taken to troubleshoot it, they sent me a replacement phone (recertified, but still) that arrived in 2 days. WAAAYYYY better than Samsung. The entire process made me a bit jealous of my wife's iPhone. If she had had a similar issue, we could have taken it to an apple store and not had the whole "our policy is that you have no phone for 7-10 business days" nonsense from Samsung AND the backup and restore process is still way better on iPhones than on any android I've ever owned. How there is no easy and reliable backup/restore mechanism on android after so long is beyond me.

Bottome line: if you have a similar issue, it's very likely a hardware problem (my replacement phone has been fine for 3 days now). And avoid Samsung support if you can!

On the second phone I still have the 2wk window to return. I am contemplating if I should just return altogether. I had bought an s21 Ultra as well and that seem to be working OK.

Two s21+ phones with same issue, what are the odds of hardware problem? But what if it is the entire batch that is bad.

 

[dougleto]

On the second phone I still have the 2wk window to return. I am contemplating if I should just return altogether. I had bought an s21 Ultra as well and that seem to be working OK.

Two s21+ phones with same issue, what are the odds of hardware problem? But what if it is the entire batch that is bad.

Your issue sounds different to me. Mine definitely fully rebooted, I have no idea what is going on with yours, it sounds like your crashes are locking the phone or something, that could definitely be software. Good luck!