PRL, or Preferred Roaming List, basically tells your phone which towers to connect to first. Changing PRLs can improve reception and data speeds, and in some cases even give you access to corporate/test towers.
Because PRLs only operate on CDMA networks, this method only applies to Sprint and Verizon (ATT and T-mobile utilize GSM networks).
Luckily for Sprint users, the method to change your PRL is very easy. All you need is a PRL file (a list at the end of this article explains them all).
- Download the PRL zip you want to use and extract the file. This will leave you with a ".prl" file.
- Place this file into the root of your internal SD card.
- Rename the file "TEST.prl".
- Unplug your phone and turn off WiFi and Data.
- Now, go to your Dialer and type ##DATA# (##3282#). This will take you to the hidden "Data Programming" menu. Go ahead and hit "View".
- Now click on "PRL Write". Your device will reboot. When you are back up, turn on Data (and WiFi if you'd like).
That's all there is to it for Sprint. But that was really easy, so let's do it the SoftModder way and expand our knowledge base of GS3 tools.
Sprint and Verizon users, as well as smaller CDMA networks (i.e. Boost) can use the DFS CDMA Tool.
What You Will Need
- A PRL file, just like before.
- The [http://www.cdmatool.com/Demo/ DFS CDMA Tool (click on the "Download" button on the top-right).
- Your MSL number (Sprint) or SPC number (Verizon, this is usually "oooooo").
Obtaining your MSL/SPC number is as easy as calling up your carrier and asking for it. They will freely give it to you. Other options include using the MSL Finder app. If that does not work, you are probably on Jelly Bean, so you will need to make a quick call to your carrier.
The use of this tool requires a non-standard USB connection (i.e. Download Mode, or just DM).
- Open the Dialer and type in ##DIAG# (##3424#).
- Click on "Qualcomm USB Settings" and select "DM + Modem + ADB" then press "OK".
- Plug your device into your PC and go to Device Manager.
- Locate "SAMSUNG Mobile USB Serial Port" and remember the COM number (in this case, COM5).
Open DFS CDMA Tool. If you are using the Demo version, there will be a small countdown and the app will launch.
- In the upper left-hand corner, hit the "Ports" button and select the port you found in Device Manger.
- Double-click the port, and double-click it on the bottom to load your device into the software.
- Enter your MSL/SPC number where it says "SPC" and hit the blue arrow. You should see the log show "Device Unlocked".
- Hit the programming tab, then the NAM sub tab.
- On the right-side, load the PRL that you want, then hit "Write".
- Disconnect your device, go back to Step 1 and put your device back to "MTP + ADB". Back out of the menu and reboot your device.
Go to Settings -> About Device -> Status. Scroll down to "PRL" and confirm that it has been changed.
- 25xxx = Residential acct - LTE/800SMR
- 24xxx = Business acct (some 3G roaming added) - LTE/800SMR
- 55xxx = Residential acct - worldphone LTE/800SMR
- 56xxx = Corporate acct (VZW 3G roaming) - worldphone LTE/800SMR
- 16xxx = Corporate acct (VZW 3G roaming) - LTE/800SMR
- 11xxx = Corporate acct (VZW 3G roaming) - no LTE/no 800SMR
- 12xxx = Corporate acct (VZW 3G roaming) - no LTE/low priority 800SMR
- 60xxx = Residential acct - no LTE/no 800SMR
- 21xxx = Residential acct - no LTE/low priority 800SMR
- Modded_VZW_PRLS - ONLY roaming (be careful, using these PRL's will mean that you will always be roaming)
Play around with various PRLs. Some people report getting the best service on very old PRLs, so really, your mileage may vary.
- Sprint users, simply go to the Dialer and type ##72786#.
- Verizon users, go to the Dialer and type **228.
Feel free to comment with any questions, concerns and tips!