nRF9160 LTE-M network registration issue

RE: nRF9160 LTE-M network registration issue

Øyvind — Wed, 21 Jan 2026 11:07:42 GMT

[quote user="Fryderyk"]Would it be possible to obtain (or is there available documentation for) the AT command sequence used by Cellular Monitor during initialization and network registration? [/quote]

Sorry, forgot to answer this question. There is documentation available for the Cellular Monitor app. This does not state directly AT commands are used, but opening a serial terminal and clicking refresh dashboard will show the commands in clear text in serial terminal for you to copy.

Kind regards,
Øyvind

RE: nRF9160 LTE-M network registration issue

Øyvind — Wed, 21 Jan 2026 11:05:35 GMT

Hello,

[quote user="Fryderyk"]We have not tried AT%XFACTORYRESET=0 yet, but this is a very good hint and we will definitely test it as a potential recovery mechanism in our firmware.[/quote]

Have you been able to try this yet?

[quote user=""]We are attaching a trace file captured using Cellular Monitor on the nRF9160 DK[/quote]

As you are using modem FW 1.3.5, are you able to test with modem FW 1.3.7 to ensure any possible fixes are included?

[quote user="Fryderyk"]We have been using SIM cards from the same distributor in Poland (Orange)[/quote]

Have you been in contact with the distributor and ensured that there is no issue with subscription or similar? As the device has been running stable for three months it does sound like an issue with the subscription. But we will need modem trace to verify or some logs, I'm afraid.

Will forward modem trace to our experts to review.

Kind regards,
Øyvind

RE: nRF9160 LTE-M network registration issue

Achim Kraus — Mon, 19 Jan 2026 08:18:03 GMT

I'm an other user. But maybe Øyvind from Nordic can help here.

RE: nRF9160 LTE-M network registration issue

Fryderyk — Mon, 19 Jan 2026 07:32:28 GMT

Hi,

thank you — these are exactly the kind of suggestions we are looking for.

We have not tried AT%XFACTORYRESET=0 yet, but this is a very good hint and we will definitely test it as a potential recovery mechanism in our firmware.

Would it be possible to obtain (or is there available documentation for) the AT command sequence used by Cellular Monitor during initialization and network registration? We would like to analyze which actions are performed there that could be responsible for bringing the SIM card back to a working state.

RE: nRF9160 LTE-M network registration issue

Achim Kraus — Sat, 17 Jan 2026 07:48:24 GMT

[quote userid="107014" url="~/f/nordic-q-a/126564/nrf9160-lte-m-network-registration-issue"]Restarting the device does not resolve the issue.[/quote]

Of course just a "guessing game" and work-around: die you try a "AT%XFACTORYRESET=0"?

AFAIK, the modem keeps some state related to the network and SIM (otherwise it would not restart that fast). Exchanging the SIM may reset that state, and so the device may be able to connect to the radio network again. A "AT%XFACTORYRESET=0" may also have a chance to reset such state. Maybe at least worth to try.

RE: nRF9160 LTE-M network registration issue

Fryderyk — Fri, 16 Jan 2026 13:09:35 GMT

We have been using SIM cards from the same distributor in Poland (Orange). This was not the first initialization of these devices with this SIM card. Our devices were operating stably for about three months, after which we suddenly experienced the issues I described earlier.

Currently, we have lost connectivity on two additional devices, which are awaiting service due to their locations. We suspect they are experiencing the same problem. The devices stopped working within just a few days.

RE: nRF9160 LTE-M network registration issue

Øyvind — Fri, 16 Jan 2026 12:49:17 GMT

Hello,

What SIM are you trying to connect with? Please note that first time initialization of SIM on network might be 15-30 minutes.

[quote user=""]only resolved after inserting a different SIM card[/quote]

Was this with a SIM of same brand or different brand as well?

Kind regards,
Øyvind