Fixed CyanogenMod random reboots on Galaxy S3

I love CyanogenMod! It is my go to ROM for any device I get. When I got my Galaxy S3 as soon as a CyanogenMod was out for it I was on it. Clean slick, and always the latest code. I use the d2att nightly builds available here. I dont always update nightly. Id say once a week or maybe every couple of weeks. In April I started experiencing CyanogenMod random reboots on my devices. In the middle of calls or while reading reedit.

I tried to updated the the latest nightly 5/15 and the install failed on some bootloader issue. I  sat down to figure out why. It turns out sometime in November AT&T pushed an update to the firmware I747UCDLK3. This update affected all the software on the phone. The modem, bootloader, and system image. Well the fact I didn’t have the bootloader updated was why the latest nightly failed. Turns out it was also why I was getting reboots. What follows is the processi used to update everything and this has completely resolved my random reboot issues.

  1. Boot into CWM Recovery and do a nandroid backup of the existing load.
  2. Rebooted into windows and installed samusng drivers.
  3. Boot the phone into recovery and wipe data and chache.
  4. (!THIS WILL ERASE INTERNAL SDCARD!Booted the phone into download mode and used Odin to load a pre-rooted stock firmware. I got it from this thread (root66_ATT_I747UCDLK3).
  5. When the phone booted into TouchWiz I took the opportunity to carrier unlock the device.
  6. From the Play Store I installed CWM ROM Manager, then used it to install the CWM Touch Recovery.
  7. I booted into CWM Recovery and wiped data and cache and restored my nandroid of the the system.
  8. Booted back to recovery and installed the latest nightly.

The Odin took about 10 minutes to complete. I Was on a USB3 port with the cable that came with the phone. There have been reports that using a USB1.1 port makes it go really slow. Don’t do that. Also dont interrupt an odin while its flashing your bootloader unless you like bricks for phones.


  1. Man my phone was jacked. I was wiping the thing and reloading the nightlys. Daily! Thanks for putting it all in one place.

      • Well, unfortunately, it did not work for me. I followed your steps exactly, but I’m still getting the random reboots. The only difference is I’m on T-Mobile (d2tmo) so maybe that’s why. Oh well, I’ve battled this issue for long enough. Looks like it’s back to stock for me.

      • Well, I had been running stock since my last post. Two days ago I decided I couldn’t tolerate TouchWiz anymore so I chose to brave the reboots and go with Cyanogenmod again. They must have fixed something in RC5 because I installed that and everything works great! No reboots!

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