Root Random Reboot on stock ROM.

[nyioo7]

Hi guys. I just bought 2 Nexus 4 for me and my girlfriend. Mine runs solid and no problems out of the box. But hers was fine until 4.2.2 upgrade. It has been randomly rebooting at least 10 to 15 times a day. It is fine when using but it seems to be rebooting at random time when not using as much. Here are the several cases of reboot.

One is, we were talking on the phone for about 2 to 3 hours and we were playing game, browsing internet, at the same time, it was fine. Then after we hang up, it reboots.

Another case is, she would leave it and not use the phone for a while and it would reboot. Happens regularly at least once at night.

It's just hard to pinpoint the problem and I have tried reflashing stock 4.2.2 on it but still no luck. I've tried turning off BT, Wifi, GPS. Still no luck. Also, after turning off Wifi, it didn't reboot but have not tested for extended period of time. Without wifi, it's kind of useless since she doesn't have data plan.

Has anyone suffered this on their phone and can custom ROM fix this? The phone hasn't been rooted or anything. It's still stock.

EDIT: Sorry if this is a repost. I couldn't search for similar topic on forums.

 

[jmar]

Hey there,

While it is hard for me to pinpoint your problem right now, we can work this out with a little troubleshooting.

Is her phone's bootloader unlocked?

Is it rooted?

When you reflashed 4.2.2, was it through a toolkit or adb, or a stock 4.2.2 ROM flashed via custom recovery?

If through recovery, did you do a full wipe of the device (except SD card) before the reflash?

Let me know what the phone looks like based on some answers there and then we can find the best course of action for you.

jmar

 

[nyioo7]

Hey. Thanks for the reply and sorry for the late reply. This is what I did when I reflashed.

I downloaded the 4.2.2 ROM from Google site. Then, I used fastboot to unlock the bootloader, then I erased bootloader, recovery, userdata, system, and cache. Then I just did flash-all as it is stated on Google site. That flashed everything including radio at once. I rebooted it and it was fine for about an hour or so. Then it restarted again. I tried formatting cache, data, system and delvik cache from custom recovery and flash the stock ROM. Still the same.

 

[jmar]

Hey. Thanks for the reply and sorry for the late reply. This is what I did when I reflashed.

I downloaded the 4.2.2 ROM from Google site. Then, I used fastboot to unlock the bootloader, then I erased bootloader, recovery, userdata, system, and cache. Then I just did flash-all as it is stated on Google site. That flashed everything including radio at once. I rebooted it and it was fine for about an hour or so. Then it restarted again. I tried formatting cache, data, system and delvik cache from custom recovery and flash the stock ROM. Still the same.

Okay, you did what I would have recommended. I don't know if the stock ROM has a reboot bug in it as I always run a custom ROM. Maybe flash a custom ROM. See if that helps. If it doesn't, I'll get someone to help assist further.

 

[nyioo7]

Last night, I flashed CM10.1 to test it. It was fine for about and hour or two. Then it restarted. First restart happened after she was on a call. Right before the call ended, it restarted. Second restarts happen while phone is on sleep. Thrid restart happened while she was playing game on the phone. So, it's just random restarting and the problem seems to be the phone itself. Maybe bad hardware? Custom ROM and stock ROM shows exact same behavior. I am going to downgrade back to 4.2.1 today and see if that solved the problem.

Any other suggestions? Thanks for the help.

 

[nyioo7]

Is there anyway to look at the log without rooting the device? Or should I root it? Also, how can I get the error log?

 

[jmar]

You need root to see the error log.

After a random reboot, using a terminal, type:

su (then hit the return button)

Then type:

cat /proc/last_kmsg > /sdcard/last_kmsg.txt (then hit the return button)

This will send a text file to the SD card. I don't know how to decipher it but this will get you the info you need.

 

[nyioo7]

Since the phone is running CM10.1 right now, it should be rooted already. Right? What is the best terminal app that will be easy to use?

 

[jmar]

I would guess that you've rooted the already.

In CM 10.1, Superuser is located near the bottom of settings. Check to see if it is there, if so, then proceed.

Terminal Emulator is what I use.

 

[nyioo7]

Well. It's my girlfriend's phone and I'm trying to keep it as stock as possible. So I didn't root it in the beginning. But now, she seems to like CM10.1 better than stock. Lol. So, I guess I was wrong about that.

Well. Weird thing. I just tried the phone to get the error log using terminal emulator (built-in with CM10.1) it says I don't have su permission. I see superuser but I don't think it's properly rooted or root may have been corrupted? I flashed it yesterday tho. I am going to try rooting using toolkit.

 

[jmar]

Well. It's my girlfriend's phone and I'm trying to keep it as stock as possible. So I didn't root it in the beginning. But now, she seems to like CM10.1 better than stock. Lol. So, I guess I was wrong about that.

Well. Weird thing. I just tried the phone to get the error log using terminal emulator (built-in with CM10.1) it says I don't have su permission. I see superuser but I don't think it's properly rooted or root may have been corrupted? I flashed it yesterday tho. I am going to try rooting using toolkit.

Good idea on the toolkit. Easy way to root.

Technically, you don't need root to flash a ROM so that explains why you don't have access to the Superuser app.

Keep me informed. Glad to be of service.

 

[nyioo7]

So, I rooted the phone. Nothing changed. Reboot still happened. I was able to teach her how to get last_kmsg from proc folder. I thought it might have been the kernel problem and tried different kernels. The last and currently running is Franco Kernel. It was fine for about 1 or 2 hours and then it rebooted. I will post link to the last_kmsg. Can anyone help me see if there's problem with kernel or not? Thanks in advance.

last_kmsg

Error happened around line 3325. It is the time of reboot. I am not sure reboot was before or after that time. I'm assuming before because after that line 3325, CPUs, LCD, Touch, etc seem to be loading up again.

 

[jmar]

So, I rooted the phone. Nothing changed. Reboot still happened. I was able to teach her how to get last_kmsg from proc folder. I thought it might have been the kernel problem and tried different kernels. The last and currently running is Franco Kernel. It was fine for about 1 or 2 hours and then it rebooted. I will post link to the last_kmsg. Can anyone help me see if there's problem with kernel or not? Thanks in advance.

last_kmsg

Error happened around line 3325. It is the time of reboot. I am not sure reboot was before or after that time. I'm assuming before because after that line 3325, CPUs, LCD, Touch, etc seem to be loading up again.

Best thing to is to post that pastebin in the Franco Kernel thread over at XDA. He will be your best resource. Plus, since you've had reboots while fully stock and completely customized, his analysis may result in him saying it isn't an issue with the kernel. Make sure to mention that you are looking for help regarding this current setup but not that you have had it while stock as well and that you aren't blaming the kernel but looking to see if the error you are experiencing is tied to the kernel or not. If it isn't, you may need to put the phone back to stock, unrooted and locked so that you can call it in for a replacement. Nothing that you've done would lead me to believe that you've damaged the phone in anyway. If you do the return, let them know that you've done factory resets with no luck. No need to mention, however, that you've rooted the phone with similar troubles.

Lastly, if you don't have an XDA account, I will post on your behalf. Let me know.

jmar

 

[nyioo7]

Hey. I have an account in XDA but I didn't post anything before so it doesn't let me post links or words longer than 3000. I tried posting this in Franco Kernel thread but that's what I got. Is there any workaround for that? How can I post this pastebin there? I don't want to trouble you by asking you to post on my behave. You've helped me a lot. Thank you for that.

 

[jmar]

Hey. I have an account in XDA but I didn't post anything before so it doesn't let me post links or words longer than 3000. I tried posting this in Franco Kernel thread but that's what I got. Is there any workaround for that? How can I post this pastebin there? I don't want to trouble you by asking you to post on my behave. You've helped me a lot. Thank you for that.

Don't worry about me helping you. If you give me your consent, I'll post it there, no problem.

 

[nyioo7]

Sure. You can post it on my behalf. I'm really appreciate it. I sent PM to Franco but I don't think he'll get it as he seems very busy according to his latest posts. Again. Thank you. If you know anyone who knows how to read kernel message, please let me know. I'll try to get some idea from them as well.

 

[jmar]

Sure. You can post it on my behalf. I'm really appreciate it. I sent PM to Franco but I don't think he'll get it as he seems very busy according to his latest posts. Again. Thank you. If you know anyone who knows how to read kernel message, please let me know. I'll try to get some idea from them as well.

Cool,

I'll check back in here if I get help. Posted for you in the kernel thread.

 

[jmar]

Are you undervolting?

 

[nyioo7]

Are you undervolting?

No. I haven't done any mod except just flash new Kernel and CM10.1. Also root. That's it.

 

[jmar]

There was a suggestion made to change to SuperSU in lieu of the built in one.

Honestly, though, I think it is something else. Can you flash back to stock, unrooted and locked once more? If it still happens, maybe it is a bad app or a defective device.

 

[nyioo7]

I'm not sure that's a good idea. The reboot got worst on stock and CM10.1 until I rooted and flashed Franco Kernel. Now, since yesterday after flashing the Kernel, there has only been 3 reboots so far. Before, it would reboot about 2 times per hour or so. I will try flashing 4.2.2 again and try using Franco Kernel with it. I will also keep it unrooted after flashing back to 4.2.2. See how that goes. I think I'm gonna have to try different combination of Kernels, and ROMs until the problem is found. If that doesn't work, I have to RMA the device.

It kinda slow to fix because I can only work on the phone when we see each other. It's almost everyday but these days, both of us are busy with school since finals are coming up very soon.

I was looking over some Kernel panic logs of other people had and usually, in the Kernel message, it says that "Kernel panic" before crashing. I triple checked the kernel log from beginning to end. Nothing like that happened. All seems to be repetitive, which means it's normal. The last thing I need to try is to go back to 4.2.1. When she first got the phone, it was fine for three days before reboots started happening. That was after 4.2.2 upgrade.

Again. Thanks for the help Jmar.

 

[nyioo7]

Hey jmar,

I have finally figured out the problem and I thought I would share the solution just in case if anyone else faces the same problem. The problem after all was the SIM card. I had to cut her SIM card to fit in the tray since it was just regular SIM card and N4 needs micro SIM card. The problem was it was kind of loose. That was causing the phone to reboot everytime it access to the SIM card.

I was finally able to pinpoint this problem because we had a fight. Lol. I was being pushy about fixing the phone and she got very frustrated. So, while we were not talking for a day, I went through some of our old chats and found out, it was not the problem until we put the SIM card in. Well, you can say that it saved the day! Haha.

I'm glad that I didn't have to do RMA which would've took way longer and it was already frustrated enough dealing with it. I think what Franco Kernel did was to lower the reboot period was the part where it uses less battery. It doesn't access to SIM card as much as stock or CM10.1. That was the reason why reboot was lessened.

Well. Thanks for all your help. If it wasn't for your inputs, I would have never figured this out.

 

[jmar]

Dude!

No friggin' way!

I can't believe that!

The phone must have, at some point, displayed a toast message at the bottom of the screen that said SIM card removed, yeah?

I'm so glad you figured it out bro. And don't worry about your girlfriend. As you gain more knowledge in troubleshooting phones, she will be more inclined to let you "tinker/fix" her devices. Trust me, my wife thinks I'm a genius.

jmar

 

[nyioo7]

Hahaha. I think it was probably doing that. But she's not very tech savvy person. So she didn't pay attention to that I guess. For my girlfriend, she's all for letting me fix her devices. It's just that when I ask her to do things, she gets frustrated when things don't work out. Lol. The last thing I asked her to do was to type the command in terminal and she couldn't because I forgot to root the phone. So, she got really frustrated with the permission denied message.

Well. All is well now. I'm really glad that I didn't buy the defective hardware N4.