You will need:
1) A rooted Nexus 4 running just about any JB 4.2/4.3 OR 4.4+ Kit Kat ROM.
2) Time and patience.
3) ES File Explorer from the Play Market
4) Baseband .33 or hybrid radio from here.
First, we’re going to need to edit a couple of files in the root (also known as /) file system. Open ES File Explorer and click the blue icon in the upper left to bring up the options menu. Expand Tools, then scroll down to Root Explorer. Select that and Allow ES File Explorer root permissions with superuser.
Another menu pops up, select Mount R/W and change BOTH from “ro” to “rw”. Save that and get back to the file system menu in ES File Explorer. Navigate your way to /system and scroll down to select the file “build.prop” Open that with ES Note Editor and select the options menu in the upper right, and click “Edit”.
Scroll approximately 3/4 of the way down through the build.prop file and locate this line of code:
Change that to look like this:
Press the back arrow in the upper left corner of ES Note Editor and it will prompt you automatically to save the file. Click yes.
THIS SECTION IS ONLY FOR T-MOBILE USERS ON 4.2 ROMS. SKIP TO THE NEXT STEP FOR 4.3 or 4.4
Cool deal. Except now, because Jellybean changed things around with how Android handles audio, the speaker for voice calls won’t work for T-Mobile users (like me). It’s OK though, because we can fix that too. Get back to ES File Explorer menu and navigate to /etc/snd_soc_msm/
LONG PRESS on the file in there, snd_soc_msm_2x blahblahblah and click More (the three dots in the lower right hand corner) and select Properties. Remember what the permissions look like! Write it down! Change permissions to rw (check all the boxes in the “read” and “write” column) and save that, going back to the snd_soc_msm folder and press back to deselect it (no check marks next to it).
Single-click on the file to open it, selecting it as a Text file and again opening it in ES Note Editor. You have to scroll down for a WHILE. ES Note Editor only loads the file incrementally (sections at a time). So just keep scrolling. It is line 1804. You are looking for a single line that says:
Change that to:
Press the upper left back button in ES Note Editor and when it prompts you, save. DO NOT leave the file yet. You should be back to just reading mode. Scroll down some more. We are looking for line 2736. It reads:
Make that read
Press back, save, then exit ES Note Editor. You’re back into the File Explorer. LONG PRESS on the snd_soc_msm_2xblahblah file and go back to it’s properties, reverting the permissions to their original state. Remember I told you to write that down? Good.
END T-MOBILE 4.2 ONLY SECTION
THE FOLLOWING APPLIES TO EVERYONE
Click the menu button in the upper left corner of ES File Explorer and select Rood Explorer again. Select Mount R/W and return / and /system to Read Only (RO). Save that and back out to your home screen.
Now go to the Phone dialer, as if you were going to make a call. Enter *#*#4636#*#*
A menu will pop up, select Phone Information. Where it says “Set preferred network type”, change that to LTE/GSM auto (PRL). Press the Home button to return to your main Android home screen.
The hardest part is done, only a couple more settings. Go to Settings>Wireless and Networks>More…>Mobile networks>Access Point Names and select your carrier, in my instance T-Mobile US, making the following changes (if necessary)
Name it something (the first field) and press the small three dots in the lower right corner to Save the APN. Reboot your N4.
When you are back to the homescreen, navigate back to Settings>Wireless and Networks>More…>Mobile networks and this time select Network Mode. It should say “WCDMA Preferred”. Change that to GSM/WCDMA/LTE. NOTE: In KitKat ROMs only, this appears to be unnecessary as 4G will already be selected under “Network Mode”.
Wait a minute or so, the signal bar should change from “H/H+” to “4G” (or LTE depending on the ROM). Yay!
Reboot to make sure everything sticks.
You should be set to go!
If you like my project, feel free to buy me a coconut water (donate). It would be greatly appreciated!
This method is confirmed to work for other cell service providers, but please do not ask for correct APN settings. Google is your friend.
This only enables LTE on Band 4 due to hardware limitations. Certain international carriers do not utilize this band. It’s up to you to find out if your region is supported.