Home/Support/Support Forum/Can't read IMEI or SIM ID
Welcome to Digi Forum, where you can ask questions and receive answers from other members of the community.

Can't read IMEI or SIM ID

+1 vote
I have about a dozen Xbee3 CAT-M1 devices that have suddenly gone dark. In all cases, they called in fine on one attempt, and failed on the next attempt, all at about the same time. On the one that I have direct access to, reading the IMEI or SIM ID returns a blank string
asked Mar 13, 2019 in Digi Connect Cellular by moranrp New to the Community (1 point)

Please log in or register to answer this question.

1 Answer

0 votes
Seems this could be a SIM provider issue. I use many of the Verizon M1 devices with no issues. I always try and update the firmware in the Digi module (even if the same version) and also the cellular firmware if possible.
answered Mar 15, 2019 by Jexx New to the Community (17 points)
I wish it were that. In the process of troubleshooting, the SIM was early in the list of things I tried. It appears that the Gecko has become unable to communicate with the underlying uBlox SARA-R4 module. Eve3n in USB-Direct mode, the uBlox module doesn't respond. These are all modules that have been running solid for a few months, deployed at various locations across the U.S., and they all died on the same morning, with the same MO. Called in once, and then never again. These are all set up in Transparent mode so, using Sleep-Pin control so, literally, all the application does is drive it to Wake and then wait for it to return an AI of 0.
Did you ever resolve this issue? I'm having the same problem even with the latest firmware release 11417 and ublox version 05.11,A02.16.
My problem turned out to be an issue with uBlox firmware, in which it would decide to occasionally run a wear-leveling algorithm on its internal flash. If you happened to pull the sleep pin while it was doing that, it would brick the device. In the end we lost about 40 units in that one event. We continue to lose units from time to time, for reasons Digi hasn't been able to explain, again apparently due to entering sleep mode. We've modified our firmware such that the device is always kept awake for at least 60 seconds at a time, which has a significant impact on our average power consumption, but seems to lessen the number of failures we see.
Thanks for the reply, that seems like what is going on but supposedly it's fixed in ublox firmware release L0.0.00.00.05.11,A.02.16 according to this: https://www.digi.com/support/knowledge-base/u-blox-memory-housekeeping-issue-on-xb3-cat-m-cell. Now I'm not sure what to believe.
Yep. Supposedly it is, and I think that the firmware update did take care of the wear-leveling issue. But I think there are still sensitivities surrounding power-down and sleep.
...