SIM Reconnection Issues (Modem Manager 1.20.4)

Aleksander Morgado aleksandermj at
Fri Mar 8 12:32:31 UTC 2024


> Recently I have encountered an issue related to reconnecting cellular.
> *OS*: Raspian OS Lite (32 bits) -> Linux panells3 6.1.0-rpi7-rpi-v8 #1
> SMP PREEMPT Debian 1:6.1.63-1+rpt1 (2023-11-24) aarch64 GNU/Linux
> *Modem*: SIM7600G-H
> The SIM is active. Using mmcli I can see that the state is connected. I
> then proceed to de-activate the SIM remotly. This is where the logs start
> (Feb 29 13:00:00).
> The logs then show a constant change in state where *enabled -> searching*
> and *searching -> enabled* is constantly logged.
> All the night is spent like this, switching the state. What I am trying to
> test is that upon remot activation of the SIM, the connection is resumed
> without problems.
> So, fast forward to Mar 01, I activate the SIM remotely and nothing
> happens. I end up reseting the modem with "mmcli -m 0 --reset" and then a
> restart of the ModemManager.service and finally the connection is
> established correctly.
> I am not sure what could be the issue. It is also worth noting that we
> have tested this in other boards that have the same modem, and the
> behaviour is not the same for every board.
Would you be able to provide full MM debug logs including the times when
the SIM was remotely deactivated and remotely activated?

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the ModemManager-devel mailing list