Here’s an updated guide on how to root your Nexus S and Nexus S 4G on Jelly Bean, ICS, Gingerbread. This new method also installs TWRP recovery instead of ClockworkMod Recovery.
Warning: Unlocking your Nexus S/Nexus S 4G will wipe your personal settings/data/internal storage!
Step 1. Power off your Nexus S or Nexus S 4G.
Step 2. Boot into fastboot mode by holding down both Volume Down and Power buttons together.
Step 3. Once in fastboot mode, connect your Nexus S/Nexus S 4G to your computer via micro-USB cable.
Step 4. For Linux and Mac, skip this step. For Windows, make sure you’ve installed correct drivers. You can watch the video tutorial on how to do this.
Once your drivers are installed, you should see “Android ADB Interface” in Device Manager.
Step 5. Download NexusSRootICS.zip and unzip to a folder called nexussrootICS.
Open up a command prompt/terminal and browse to the directory by typing:
Next, type the following to unlock your Nexus S/Nexus S 4G:
fastboot oem unlock
./fastboot-mac oem unlock
./fastboot-linux oem unlock
Step 6. Hit the Volume Up button once and then the Power button to unlock your Nexus S/Nexus S 4G.
Step 7. Your screen should now say, “LOCK STATE – UNLOCKED”.
Step 8. Next, type the following for Nexus S:
fastboot flash recovery twrp-crespo-2.0.0RC0.img
./fastboot-mac flash recovery twrp-crespo-2.0.0RC0.img
./fastboot-linux flash recovery twrp-crespo-2.0.0RC0.img
For Nexus S 4G, type the following instead:
fastboot flash recovery twrp-crespo4g-2.0.0RC0.img
./fastboot-mac flash recovery twrp-crespo4g-2.0.0RC0.img
./fastboot-linux flash recovery twrp-crespo4g-2.0.0RC0.img
Step 9. You can now go into Recovery by choosing RECOVERY from the fastboot menu.
Step 10. Next choose “Mount”.
Step 11. Choose “Mount USB Storage”.
Step 12. Copy the SuperUser.zip to the internal storage of your Nexus S/Nexus S 4G.
Step 13. Choose “Unmount” on your Nexus S/Nexus S 4G.
Step 14. Choose “Install”.
Step 15. Choose “SuperUser.zip”.
Step 16. Choose “Flash now”.
Step 17. Choose “Reboot System” and reboot system.
Step 18. Your Nexus S/Nexus S 4G should now show the Superuser app, congrats you’ve successfully rooted your Nexus S/Nexus S 4G!
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You will need a rooted Nexus S to install all ROM/kernels.
NOTE: PLEASE ONLY INSTALL ROMS INTENDED FOR YOUR VERSION OF Nexus S! Otherwise you WILL BRICK YOUR PHONE and I will not be responsible!
How to Root Nexus S!
First time to rooting and custom ROMs? Please see our Nexus S FAQ FIRST! Nexus S ROMs
Nexus S ROMs
Nexus S 4G ROMs