TC63I Revision A200 modem receives zero data | Telit Cinterion IoT Developer Community

Hello forum - hope you can assist in my problem,

We are using the TC63I modem in our applcation and experience a large amount of modems that fails to receive any data. Our installations are a mix of revision A100 and A200, but only the model A200 is failing - the model A100 works fine.  It is important to say that the A200 has been working fine for a period of approx one year before they syddenly stops working. Below debugging of the AT command trafic between modems and our SW application shows that the A200 modem contains zero data in its reply, where the A100 contains data.

A100 (everything is OK)

^SISI: 0,4,0,0,0,0

OK

at^sisw=0,16

^SISW: 0, 16, 16

OK

at^sisr=0,64

^SISR: 0, 16

      (#

OK

A200 (zero data in SISR command)

^SISI: 0,4,0,0,0,0

OK

at^sisw=0,16

^SISW: 0, 16, 16

OK

at^sisr=0,64

^SISR: 0, 0

OK

I noticed that if I flash the A200 modem with the same firmware again (02.004) then the reply once again contains data and everything works fine. We are not able to dismount every modem and flash it, so I´m hopping that you could suggest a number of AT commands that will bring the modem back on track.

Thanks