The nRF9160 modem is preprogrammed with a firmware that supports the AT commands functionality needed for recommended production testing. The version of the preprogrammed firmware can change over time. The firmware must be updated to a complete modem firmware that is product-certified. You can check the version of the preprogrammed modem firmware with the %SHORTSWVER AT command. For more information, see Short software identification %SHORTSWVER in nRF91 AT Commands Reference Guide. For available firmware releases, see nRF9160 Downloads.
For information on programming using a customized setup in production, see Updating the modem in nAN41 - nRF9160 Production Programming and nrfjprog executable or DLL in nRF Command Line Tools.
To update the modem firmware, connect nRF9160's Serial Wire Debug (SWD) interface to a debugger. Commercially available programming units, such as SEGGER J-Link, can be used.