Modem thinks that SIM is removed, while it is in

IoT Gateways Legacy FX/FXT series
1

I am seing some strange behaviour on FXT009 and FXT003, both running 7.45 f/w

SIM is in, but AT+WSHS command returns 0 (SIM holder status). Internally, our application is subscribed to SIM service and we get status SIM_REMOVED. On FXT-009 modem refused to register. On FXT003, modem happily registered, while reporting missing SIM. My guess is that problem is in OpenAT f/w and in FXT-003 registration is done purely by ICERA processor and it does not care about SIM holder status.

Issue is only seen on two modems so far. In both cases issue popped up after we used AT+WDWL command to load software. One of the units is running purely OpenAT, user application turned off. I loaded 7.45.1 before problem started, then 7.46, then downgrading back to 7.45.0 and problem was still there. On the second modem we were downloading new version of our application.
Unfortunately, both modems are not on my desk (both are couple of thouthands km away). When I tried same procedure on the modems I have here, no issues were observed.
Problem modems are not in same place. In fact they are in different countries.

The only way for me to get modems to register again was to disable SIMREMOVAL feature (at+wfm=0,7).

Did anyone observed a problem like that?

Thanks,
Rudolf

2

I’m getting the same behaviour on my FXT003 . Using the Discovery Tool.

However, I’m still fumbling with this modem trying to get something up and running :slight_smile: https://forum.sierrawireless.com/t/fxt003-get-up-and-running/5344/1

3

OK,

  1. Seems that FXT series modems have issues with SIM switch when Ethernet IESM card is installed. Switch may not work properly (mechanically). Try to remove the plate covering SIM holder and see if problem is fixed.

  2. Temporary fix is AT+WFM=0,7 command. This turns off SIM Detection mechanism. As far as I understand, disabling this feature does not allow for “hot swap” of SIM card, but SIM detection does not depend on the switch state anymore.

Rudolf

4

I found these commands got my FXT003 to recognise the SIM

AT+CMEE=1
AT&W
AT+CFUN=1

hope it helps

5

Thanks,

The command you so simply turn on extended error reporting. The fact your SIm got working is a coincidence.

Sierra Wireless had issue in production that is supposedly resolved now. SIM switch would fail mechanically after installation of Ethernet IESM card and face plate. There is a report available from Sierra wireless explaining the issue and possible workarounds

Rudolf