Enable T-Mobile HSPA+ AWS Bands on AT&T Galaxy S4 SGH-i337 / SGH-i337M


Following this guide, you will learn how to enable T-Mobile HSPA+ AWS bands (bands used by T-Mobile for 3G/4G HSPA+ service) on your AT&T Samsung Galaxy S4 smartphone models: SGH-i337 and Canadian SGH-i337M. This way you will be able to receive the 3G/4G HSPA+ data using a T-Mobile (and any other Canadian networks supporting AWS) SIM card. Which essentially means that your AT&T Samsung Galaxy S4 will turn into a fully functional T-Mobile Galaxy S4!

How to enable T-Mobile HSPA+ AWS Bands on AT&T Galaxy S4 smartphones:

Required files: Download Phone Utility app and install the phoneutil.apk.

  • Dial *#7284# on your phone dialer and choose Qualcomm USB Settings.
  • Select RNDIS + DM + MODEM and tap on OK.
  • Connect your SGS4 to your computer using a USB cable. For that ensure that you have Samsung drivers installed on your PC.  You should be able to see SAMSUNG Mobile USB Serial Port under Ports in Device Manager.
  • Next, download QPST program on your PC and run the exe file to install QPST.
  • Also, download the QCN file with AWS enabled for SGH-i337/SGH-i337M.
  • Run the QPST Program now on your computer and click on Add New Port under Ports tab.
  • Select the COM port that you saw earlier in Device Manager. In case you have more than one, just try anyone of them first and click on OK.
  • If you get a No Phone message then try adding another COM port. If you see (0), then this would be the COM port you will be using.
  • Now go to Start Clients (from tabs) > SOFTWARE DOWNLOAD.
  • Click on the Backup tab and choose your COM port. Locate QCN file and hit Start. This step will backup your current NV memory. In case if something goes haywire, you would have the option to always restore the original NV memory.
  • Now choose Restore tab and locate the QCN file 337_AWS.qcn you downloaded earlier and click on Start. The process of flashing the AWS bands enabled QCN will initiate now.
  • Your phone will reboot automatically. After that's done, you should be able to pick up AWS bands.

Try using the T-Mobile SIM in your AT&T Galaxy S4 and it will pick up HSPA+ signals from the t-m just fine!