Help S2 keeps rebooting

ceider said:

Oops, thought I had replied here. Since taking the memory card out, I've had no mysterious reboot issues.

The card is nearly two years old and had been used in a HTC desire. Perhaps something lurking on there caused it. I suppose I don't really need one since the phone works without....and the internal memory is massive. For my usage anyway.

Anyone use a memory card with NO problems? I'm wondering if something else will go wrong with the handset down the road

Click to expand...

I also had frequent reboots. When I took out my 16 GB SandDisk card (never tried replacing it as I haven't really needed the extra space) they stopped.
I've had a few in the months since then, but they've been very rare, where before with the card in it I was more or less getting daily random reboots.

I took the memory card out again last night and just this moment I had the usual reboot. Not happy.

I noticed that a little memory card symbol appeared in the left notification bar when I restart the phone. Does anybody know what that means??

I get the feeling that has something to do with the issue. But it vanished before I could see what it was

Really, why is that memory card symbol popping up when there's no card in there??

I put it back in touch test it, as last night I didn't unmount it before taking it out...just in case that was something to do with the reboot. Turned it back on, and the symbol came up!

At this rate I will be looking for o2 to give me a new phone

ceider said:

I noticed that a little memory card symbol appeared in the left notification bar when I restart the phone. Does anybody know what that means??

Click to expand...

The icon actually indicates the scanning of your internal sd storage and it is a normal circumstance whenever your phone is rebooted or switched on.

wengyew90 said:

The icon actually indicates the scanning of your internal sd storage and it is a normal circumstance whenever your phone is rebooted or switched on.

Click to expand...

Thanks. So its really just the phone searching for sd card....

Had another reboot today, with no sd card in the phone. Will give it another week and if it continues, I'll be phoning o2 :/

Thought I'd get through the day without any problems but no.

I occasionally get warnings about kworker from battery stats, and I have little idea what it is apart from the fact it has something to do with the kernel...I'm not rooted btw.

Given the fact that the phone has already been "repaired", And upgraded and it's still happening, I must just have a complete dud of a phone?

Well, after factory resetting on 15 June, without inserting my old memory card, my phone now has 175+ hours without rebooting, once.

The only app that I can think of that I did not reinstall was Fontomizer SP. I wonder.....

Finally sorted

My phone has had ICS for about three months now and hasn't rebooted since. Strange when some other people said their problems started with ICS. Anyway I'm not complaining!!! VBG

Samsung really does need to get on top of this problem though - it is obviously affecting many people.

I finally fixed mine. 02 replaced the handset and its been great ever since. In fact this one seems to be better at battery life.

dafi said:

My phone has had ICS for about three months now and hasn't rebooted since. Strange when some other people said their problems started with ICS. Anyway I'm not complaining!!! VBG

Samsung really does need to get on top of this problem though - it is obviously affecting many people.

Click to expand...

My trouble started long before ICS., and continued after. Seems I had to sort it myself. I'm encouraged that O2 actually replaced a handset, so should it happen again, they can take this back!

Exchanging my phone tomorrow for a new one with o2. The phone wasn't playing up as badly as before, but crashing randomly, always from idle. Just now it switched itself right off and I couldn't get it back on until I took the battery out. It also took a good few minutes before it would allow me to input my pin number. No amount of typing would bring the pin no up.

Bloody good riddance.

Ps, has anyone ever heard of a sim card causing these problems. That's the first thing that was suggested to me today, a new sim card. WTF??

New phone yesterday. Twice already today has the phone crashed, the same as usual. Really very pissed off and fed up with this. It's fast becoming the worst handset I've ever owned.

No memory card in right now. Really, can a faulty SIM CARD cause these sorts of problems?

It could just be the faulty firmware or apps. Same thing happens to me. It either crashes once every few days or few times in a day.

The replacement phone I got actually seems worse than the original phone I returned. 3 times in the past day it shut off completely and wouldn't turn back on til the battery was taken out. That's happened about 6 times this week.

Anyone with this problem ever managed to find a permanent solution? If I argue enough with O2 in still doubt they'll let me change handset altogether

This problime hapend to me. And at the first I started testing whay.
after word, I found that when I move the SD out, the phone works ok.
then I started to move all applications from the sd option to the phone.
that fixed it.
then I started to test all application found a lot of uncompatible apps but I left the on, as lone the restarting is now done.

Remove all your apps to the phone, if any of them is on the sd. and check will it fix it or not.....

Turns out the problem could well be Juice Defender. On my third phone, and installed all my usual apps the first day. within an hour of updating everything, off it went. I since read comments on market that others have had problems with JD. So I won't be installing that again.

However I did have a shutdown after I had trouble connecting to wifi a few days later. I've seen others over on XDA with this problem. Some have commented that anything that tries to control wifi behaviour/access will result in this problem for some phones. Looks like all of them in my case.

I've rooted my phone, and have been wary of wifi connection problems at home, and since last Friday, I've not had a reboot issue once.

3 months old S2 just starting rebooting. could not factory reset as was not getting keyboard. just got to reset at last. hoping it works now

Hello All,

Just found this thread to ask if anyone has found out solution what is wrong with the phone when it's doing this random rebooting? I've had S2 for month now and I'm so pissed with this phone for freezing and then rebooting (I think watchdog will reboot it when it is not responding). I can't seem to find any obvious reason why this happen. I've done hard reset and emptied cache... Sometimes there might go day that it doesn't and sometimes it reboots every ten minutes or so. It sounds to me that it has defect ram memory. If it tries to use that defected part of memory it freezes.

I brought it back to dealer and they sent it to repair. As this issue is hard to reproduce I think they just reinstall firmware and return that defected phone.. We'll see.

Edit: I don't have external SD card, Android version 4.0.4, Certainly I'm not pressing power button when this occurs.

Definitely factory reset is not the solution as I had tried doing it 2 times and still the problem recurred. It could be the problem of the firmware version which render it invompatible with certsin apps

Before the phone reboots I get a popup box which says: Because google's limits, The following apps cannot be killed. Please click to force close from application info. It then lists one to three apps (variable names each time but mostly yahoo mail and yahoo messenger are listed). I do have over 300 apps on my SD card and have removed listed apps when I get the chance. When SD card removed phone is ok but only phone apps available. So it is a random reboot when SD card is in. Left it a couple of times plugged into charger in a cool place - it rebooted over 1000 minutes before stabilising! RANDOM

Just to chime in on this. My S2 is running 4.0.3 that I updated it to about a month ago or so. I bought it on the first of September but it was second hand so I dont know how old it actually is. It had 2.3.3 when I bought it.

Last week on Wednesday, it rebooted 4 times when I was at work in the space of about a half hour. I switched it off for about an hour and that seemed to stop it. Unfortunately it did it again 5 times on Friday night and it was sitting up on a table when it did it this time so it wasnt any buttons being pressed that caused it.

It really took a dive on Saturday morning though. The story is in this thread... http://androidforums.com/samsung-galaxy-s2-international/640536-galaxy-s2-issues.html

...so I had to do a factory reset. Hopefully that killed 2 birds with the one stone as it has been behaving itself since.

My device, the S2, reboots out of nothing even when left alone on the table. Updated to ICS, no changes. So, I performed a factory reset (which to my surprise didn't restored the original Android 2.x version but the ICS one I've installed before). During the factory reset I choose to not reinstall any of the app I had and I choose to format the SD card.

I used the phone for two days and no reboot. Before they happened several times a day. So, I installed my first app, the Dolphin browser and all ok. A couple of days later I installed google reader and the phone started to reboot. Uninstalled it and the reboots are gone. A couple of days later I installed dropbox and reboots again. Uninstall, once more.

Before the factory reset I had notice already that any time I installed dropbox, things went bad, so again this was the scenario.

So far, I have detected two app that were crashing the phone. Let's see how it goes. If any body has feedback, please post it.

Yes, I had once a problem with the SIM card. The phone was taking a couple of minutes to become available after turned on.

Hey all,

This thread seems to be a good place to get my own frustration out on the reboot problem. I will add some details so you all might benefit from that.

I have owned my Galaxy S2 for over a year now and have experienced several firmware versions. I ran on 2.3.4 for a while without any big problems. I got a little obsessed by maximizing the batt life so I played around with Juice Defender and Juice plotter and got some good results. Side effect was that I noticed weird behavior immediately since I was focussing on my battery drain and what programs were responsible for that. Juice plotter is very useful here.

What I noticed on that firmware version was that my phone sometimes got into a state that drained the battery quickly. As a reference:

Normal: battery could last 48 hours with moderate use
Charging rate: 25% per hour
Abnormal discharging: 10% per hour with no clear apps causing this (phone idle)

I also noticed during this abnormal drain the phone would get really warm. Not sure if that is the battery or the CPU. I am guessing the CPU.
It seemed like such an episode started when I got a phonecall when my phone was on the charger. Like something went wrong during that combination. A manual reboot usually solved it and battery drain went back to normal.

I accepted this behavior and lived with it for a while.

So, then ICS came about. I waited with the upgrade due to a lot of issues on the web. Thought a little legging behind wouldn;t hurt.. Finally, I decided to upgrade and did it the clean way: factory reset.

That was quite some work since all my apps were gone, all my settings were gone and I didn't want to re-use any restored settings when they were offered.

After the upgrade, I think it was 4.0.2, I immediately had serious problems with my phone and battery drain. My phone regularly was 'dead' when I tried to use it. I could reboot it after holding the power button for a while (5 - 10 seconds). I am guessing this is hard reboot like any normal PC, usefull when it 'hangs'.

When looking at Juiceplotter, the battery level made huge jumps, where the level changed by 30% within a short time (hour or so) and the phone was off. At least that is what it looks like because Juiceplotter is not logging any information so that part of the graph is unavailable.

I removed the battery as a last resort and... it seemed to solve the problem. My phone ran for a week with normal power behavior.

Soon after I solved this I got 2 other upgrades pushed on my phone and ended up with the current 4.0.4. version. Since then (2 months), the behavior has been erratic in waves. Sometimes it runs fine for several days, sometimes it dies twice a day.

During normal operation the battery drain is very good (=low). ICS definately improved when everything is working as it should. As a benchmark:
Battery lasts 72 hours.
Usage: 5 hours of GPS, 4 short phone calls, regular e-mail check.
JD ultimate settings: ping on 30 minute interval, auto connect WIFI at home and at work, nightschedule 00:00 - 07:00

However, when things go wrong it totally sucks! The behavior is always the same:
- Phone seems dead when pushing the home button or power button
- Long press (5 - 10 sec) of the powerbutton forces a reboot
- The phone feels warm to the touch, some process is draining battery fast (20 - 30 % per hour).
- After the battery is dead, in 1 - 3 hours depending on your starting level, the phone obviously is not warm anymore, does not wake up when long pressing the power button and the only solution is to put it on the charger. This will show a battery level of 1 or 2 % with a warning 'critically low'.
- When looking at Juiceplotter, the graph ends after an 'idle' period where battery drain is very low. Then it starts again at the point you have revived it and there is a huge uncharted drop in battery level.
- When looking at the battery stats of android, there is sometimes an app that jumps out with its battery usage. It is never the same app though and de-installing it does not solve the problem.

My conclusion:
- ICS has a serious bug that is not caused by a clash of old firmware leftovers.
- The bug has been there from the first version of ICS.
- The bug seems to freeze random background processes on the phone and causes the CPU to work overtime and use a lot of power.
- When the battery is not fully depleted, a hard reboot helps (long press power button).
- After the battery is fully drained, only recharging will revive your phone.
- During the 'freeze' period the OS totally 'hangs'. None of the apps are able to log anything anymore and it looks like the phone is turned off.

So no solution from me, maybe some piece of mind that you all are not crazy.

tux1968 said:

So far, I have detected two app that were crashing the phone. Let's see how it goes. If any body has feedback, please post it.

Click to expand...

Another reset without any new app. I begin to suspect that the problem it's not related with the apps.