2G / 3G Registration problem with GE 865

12 thoughts on “2G / 3G Registration problem with GE 865

  1. Hi All,

    I am using the GE 865 with rel 10.001 in Ireland and UK. We are seeing a problem with some new vodafone SIMs – these are off the shelf SIMs not tailored for M2M. In phones they work and allow registration even when the phone is in ‘force 2g’ mode. They work in some other M2M Modems. But they do not allow my Telit GE 865 to register. I couldn’t get anyone technical enough in Vodafone to help debug the issue, other than the standard first line tech support who weren’t technical enough and just tell me ‘it should work’.

    One colleague in the industry suggested that it might be that the Telit FW is capable of only reading the 2G profile from the SIM and that the network is not implementing C2 and C3 conversion algorithms (for the tuples of authentication keys etc). I’m not a GSM expert so I cannot confirm this.

    If use older Vodafone SIMs or SIMs from other networks, for example O2/Three, it works.

    Any idea what might be wrong or what kind of diagnostic might help identify the problem. I messed around a bit with the CRSM command but I’m not entirely sure what the output  of the 242 stat is.

    Thanks for suggestions,


      1. Fantastic, yes, setting ENAUSIM to 1 makes it work after a power cycle. From what I gather this enables some kind of “USIM Application” which alters how the ME can interact with the profiles.

        Can you offer me more information please? Or point me to a good explanation.

        But a key question, is there any adverse side effect of having USIM = 1 (otherwise why would the feature ever be turned off)



        1. About  more info:

          please give a look at the Enable USIM application – #ENAUSIM  in the  Telit_AT_Commands_Reference_Guide_r21.pdf.

          Regarding the key question, please read the description of the command in the above user guide.

          When the 2g products started to be produced the USIM didn’t exist. so this is the default setting for backward compatibility

          1. Thank you Luca.

            At the moment I only have r20 of the AT Commands doc, but it does give an overview of the ENUSIM command, thanks.

            From you reply, I undertand then that there is no negative side-effect of always setting ENAUSIM=1,  and that with this setting, my devices in the field will work with all SIMs, new (2G only) and old (2G + 3G) USIMs.

            Thanks again,


          2. Hi Luca,

            I have found a side-effect of turning on my USIM all the time! On most of my SIMs, the SIM now asks for a PIN. This is bizarre – the SIMs in question work perfectly with USIM turned off and were deliberately provisioned not to need a pin (m2m SIMs). When I turn off USIM again (ENAUSIM=0 and reboot) the SIM operates and asks for no PIN. Put the SIM in a phone, and it operates normally without PIN.

            Have you any idea what is going on? Thank you.


          3. please,

            send a log of the AT commands and answers. Other than the other commands, please send these commands: at+cimi, at+cgsn, at+cgmr

          4. please,

            send a log of the AT commands and answers. Other than the other commands, please send these commands: at+cimi, at+cgsn, at+cgmr

          5. AT#ENAUSIM?
            #ENAUSIM: 1

            +CPIN: SIM PIN

            +CME ERROR: SIM PIN required



            # Now turn off USIM and reboot
            #ENAUSIM: 1

            +CPIN: READY


          6. Hi,

            with enausim enabled you enable another part of the SIM (the “3g” part). So it could be possible to have a different request.

            regarding the phone you have tested with success: which model is it ?

          7. An oldish Nokia E52.

            But I have made another observation – you’ll see in the trace the firmware version is 10.00.005. I have another Telit unit here that is 10.01.000 and it DOES NOT have the same problem. That is to say, it does not ask for the SIM PIN.

            It seems to me there is a difference in the way the USIM protocol is handled between 10.01.000 and 10.00.005.

            Can you confirm if that is the case?