Hello.
We have a modem MC60, version MC60CAR01A05.
There is a plastic sim card euicc connected to AT+QDSIM=0 and an esim (on chip) connected to AT+QDSIM=1 which we don’t use anymore.
At power on, always and only the SIM 0 (plastic) is selected.
We can register normally to the network, read the active imsi etc.. no problems here.
This sim has 2 imsi internally, which uses based on country.
There is an applet running in the sim, which in case of failed registration attempt, starts a timer internally (up to 5 minutes) which switches the imsi to the second one.
During the switch, a +CREG: 0,3 is returned (roaming not allowed) and this should last until the sim switches imsis, then the modem connects again giving +CREG: 0,5.
The problem is that we don’t see this switch when using the MC60, we send AT+CREG? every 10 seconds for more than 5 minutes, but nothing happens. IMSI is still the same, +CREG: remains 0,3.
Note that this problem happens ONLY on this MC60, because If I put the sim card in any other modem (ublox SARA, SIM900, mobile phone, etc..) the sim actually switches the imsi correctly.
I suspect there is something preventing the sim to switch, but I’m not sure what.
I also found out some AT+QCFG commands I could send (SIM/Reset), sim/Type etc… would these be helpful to let the sim card countdown to switch?
Is there anything else that could prevent the applet to switch the imsi?
There is nothing wrong with the sim itself, as it works with other modems.
Any hint or advice will be extremely helpful and more than welcome.
Thanks a lot.