Sign in

Log in to My Sprint

Log in to My Sprint

Sign up for a My Sprint profile

  • Monitor data usage
  • View or pay bills
  • Update account preferences
  • Get custom deals and offers

Troubleshoot issues related to SIM card not detected or cannot be read on your Franklin U772 USB Modem

Last Updated: Jul 22, 2016

This article helps troubleshoot SIM card not detected or cannot be read error on your Franklin U772 USB Modem.

You may have SIM card detection or reading issues if your device:

  • Does not detect the SIM card
  • Cannot read the SIM card
  • Can connect to the 3G network but cannot connect to the 4G LTE network

These steps help identify and resolve the underlying cause. After completing each step, test to see if the issue is fixed. If you have uncovered an issue that you can't fix, make an appointment at a convenient Sprint Repair center for more help.

  1. Perform a soft reset.

    1. Unplug the device from the USB port on your computer.
    2. After 10 seconds, plug the device into the USB port on your computer.
  2. Remove the SIM card, clean the SIM slot and reinsert the SIM card.

    1. Unplug the device from the USB port on your computer.
    2. Slide down the SIM card cover located in the back of the device.
    3. Remove the SIM card by sliding it down out of the slot.
    4. Clean the SIM card slot and SIM card of any loose debris or dirt using a soft lint free cloth or compressed air.
    5. Reinsert the SIM card by sliding it into the slot with the notch at the bottom right and the gold contacts facing the device.
    6. Reattach the SIM card cover by sliding it up to snap it into place.
    7. Plug the device into the USB port on your computer.
  3. Perform a master reset.

    This type of reset should only be used as a last resort after all other troubleshooting steps have been exhausted.

    1. In your Internet browser, type http://sprintmodem or http://192.168.10.1 in the address bar.
    2. Press Enter.
    3. Enter the Administrator password in the Password field and click OK.

      Note: The default password is admin.

    4. Click Settings.
    5. Click Advanced Settings.
    6. Click Equipment.
    7. Enter the MSL, then click OK.
    8. Click Equipment one more time, then click RTN.
    9. Click Reset.
    10. Review the warning and click YES.
    11. The device will restart and the activation will begin.

If you're still having issues, please try the Sprint Community pages or make an appointment at a convenient Sprint Repair center for more help.

Be the first to Rate this article

My rating

Contact us

Find a store


Recently Viewed