nRF9160 does not connect to network

[ralphvn]

I have a nRF9160-DK but it will not connect to the network. I also have a Thingy:91 that will connect to the network.

Thingy:91 test:

> AT+CEREG=5

OK
> AT+CSCON=1

OK
> AT%XSYSTEMMODE=1,1,1,0

OK
> AT+CFUN=1

OK

+CEREG: 2,"7B0D","000A150C",7

+CSCON: 1

+CEREG: 1,"7B0D","000A150C",7,,,"00001010","11000010"

+CSCON: 0

nRF9160-DK test:

> AT+CEREG=5

OK
> AT+CSCON=1

OK
> AT%XSYSTEMMODE=1,1,1,0

OK
> AT+CFUN=1

OK

+CEREG: 2,"7B0D","000A150C",7

The nRF9160-DK is stuck on stat 2, "2 – Not registered, but UE is currently trying to attach or searching an operator to register to", while the Thingy:91 with the same simcard will go to stat 1, "1 – Registered, home network".

What can be the problem and how to fix this, having the problem with the nRF9160-DK all day now and for debugging purposes I programmed them both with newest modem firmware and Serial LTE Modem to find out this difference with the same simcard at the same location?

[ralphvn]

trace-2023-12-14T16-09-32.098Z.mtrace

Fullscreen serial-terminal-2023-12-14T162411.115Z.txt Download

> AT+CFUN=1
OK
> AT%XCONNSTAT=1
OK
> AT%XCONNSTAT?
%XCONNSTAT: 0,0,0,0,0,0
OK
> AT+CMEE=1
OK
> AT%XSIM=1
OK
> AT+CEREG=5
OK
> AT%MDMEV=1
OK
> AT%CESQ=1
OK
> AT+CGSN=1
+CGSN: "351901930758119"
OK
> AT+CGMM
nRF9160-SICA
OK
> AT+CEMODE?
+CEMODE: 2
OK
> AT+CMEE?
+CMEE: 1
OK
> AT+CNEC?
+CNEC: 0
OK
> AT+CGEREP?
+CGEREP: 0,0
OK
> AT+CIND=1,1,1
OK
> AT+COPS=3,2
OK
> AT+CGDCONT?
OK
> AT+CGACT?
OK
> AT+CESQ
+CESQ: 99,99,255,255,255,255
OK
> AT%XSIM?
%XSIM: 0
OK
> AT+CPIN?
+CME ERROR: 13
> AT+CIMI
+CME ERROR: 0
> AT+CNEC=24
OK
> AT+CEER
OK
> AT+CGEREP=1
OK
> AT%XPOFWARN=1,30
OK
> AT%XVBATLVL=1
OK
> AT+CGMI
Nordic Semiconductor ASA
OK
> AT+CGMR
mfw_nrf9160_1.3.5
OK
> AT+CGSN
351901930758119
OK
> AT%XMODEMUUID
%XMODEMUUID: dc8e7aff-5331-409e-be02-5529dffa5537
OK
> AT%XDATAPRFL?
%XDATAPRFL: 2
OK
> AT+CEREG?
+CEREG: 5,4
OK
> AT+CFUN?
+CFUN: 1
OK
> AT%CESQ=1
OK
> AT+CSCON=1
OK
> AT+CSCON?
+CSCON: 1,0
OK
> AT+CPAS
+CPAS: 0
OK
> AT+CEDRXRDP
+CEDRXRDP: 0
OK
> AT%XTIME=1
OK
> AT%CONEVAL
%CONEVAL: 1
OK
> AT%XCBAND=?
%XCBAND: (1,2,3,4,5,8,12,13,18,19,20,25,26,28,66)
OK
> AT%XCBAND
%XCBAND: 0
OK
> AT%HWVERSION
%HWVERSION: nRF9160 SICA B1A
OK
> AT%XMODEMTRACE=1,2
OK
> AT%XSYSTEMMODE?
%XSYSTEMMODE: 1,1,1,0
OK
> AT%XICCID
%XICCID: 8931082122043281303F
OK
> AT%XEMPR?
%XEMPR:
OK
> AT+CGDCONT?
OK
> AT+COPS?
+COPS: 0
OK
> AT%XMONITOR
%XMONITOR: 4
OK
> AT+CPINR="SIM PIN"
+CPINR: "SIM PIN",5
OK
%XSIM: 1> AT+CPINR="SIM PIN2"
+CPINR: "SIM PIN2",3
OK
> AT+CPINR="SIM PUK"
+CPINR: "SIM PUK",10
OK
> AT+CPINR="SIM PUK2"
+CPINR: "SIM PUK2",10
OK
> AT%XSIM?
%XSIM: 1
OK
%CESQ: 41,2,7,1
%MDMEV: RESET LOOP
+CEREG: 2,"7B0D","000A150C",7
%CESQ: 47,2,14,2
%CESQ: 46,2,19,2
%CESQ: 45,2,13,1
%CESQ: 46,2,18,2
%CESQ: 44,2,12,1
%CESQ: 45,2,18,2
%CESQ: 45,2,13,1
%CESQ: 46,2,18,2
%CESQ: 46,2,13,1
%CESQ: 46,2,18,2
%CESQ: 45,2,13,1
%CESQ: 44,2,18,2
%CESQ: 47,2,13,1
%CESQ: 48,2,19,2
%CESQ: 48,2,14,2
%CESQ: 48,2,19,2
%CESQ: 47,2,14,2
%CESQ: 48,2,19,2
%CESQ: 47,2,14,2
%CESQ: 48,2,19,2
%CESQ: 47,2,14,2
%CESQ: 47,2,19,2
%CESQ: 47,2,14,2
%CESQ: 48,2,19,2
%CESQ: 47,2,14,2
%CESQ: 47,2,19,2
%CESQ: 47,2,14,2
%CESQ: 47,2,19,2
%CESQ: 47,2,14,2
%CESQ: 47,2,19,2
%CESQ: 47,2,14,2
%CESQ: 46,2,19,2
%CESQ: 46,2,14,2
%CESQ: 47,2,19,2
%CESQ: 46,2,14,2
%CESQ: 47,2,19,2
+CSCON: 1
+CGEV: ME PDN ACT 0,0
+CNEC_ESM: 50,0
%MDMEV: SEARCH STATUS 2
+CEREG: 1,"7B0D","000A150C",7,,,"11100000","11100000"
+CIND: "service",1
%XTIME: "40","32214161322140","00"
+CSCON: 0
%CESQ: 48,2,14,2
%CESQ: 48,2,19,2
%CESQ: 48,2,14,2
%CESQ: 47,2,19,2

This is the modem trace and debug output. I started working after about 15 minutes. It looks like there is something going wrong with the simcard I think.

> AT+CPIN?

+CME ERROR: 13
> AT+CIMI

+CME ERROR: 0

And maybe there is some kind of simcard retry after 15 minutes? But still strang it starts working after 15 minutes without touching it and when I press the reset button it won't work anymore after the reboot.

I tried with an own simcard and with the provided iBasis sim, both same result.

[Øyvind]

Thanks for providing the modem trace. Yes, it does seems like there is an issue with the SIM. CME ERROR 13 SIM failure. Will need to investigate why the nRF9160DK returns this, and not the Thingy:91

You are also getting a modem reset loop. From Modem domain event notification %MDMEV: 

RESET LOOP indicates that the modem restricts Attach attempts for the next 30 minutes. The timer does not run when the modem has no power or while it stays in the reset loop. The modem counts all the resets where the modem is not gracefully deinitialized with +CFUN=0.

If there are more than five resets, reset loop restriction is activated.v1.3.0

If there are more than seven resets, reset loop restriction is activated.v1.3.x≥1

For more information on reset loop, see nWP042 - nRF9160 Modem Reset Loop Restriction.

From the white paper linked above:

The activation of the reset loop restriction starts the timer with a 30 minute period. During this time, the modem blocks all Attach attempts. After the timer has expired, the modem starts normal behavior and automatically regains LTE service for possible connections the same way as when the modem is activated without the reset loop restriction.

ralphvn said:

The sticker at the back says PCA10090, 1.1.3 and 2023.31.

That is perfect! Will forward this with the modem trace. 

Could you test with the Asset Tracker application as well? (I assume there will not be any change)

Kind regards,
Øyvind

[ralphvn]

Thanks for your answer, I think the CME ERROR is a minor thing and the root cause of my problems is in the RESET LOOP.

In the attachment you can see the Asset Tracker has the same problem with the RESET LOOP. It says 'Power-cycle the device to circumvent this restriction.' but the documentation you send says 'When the reset count reaches the limit, the blocking restriction is written to Non-volatile Memory (NVM). The wait time cannot be bypassed after the wait has started. If the modem is reset during the wait period, the wait period is restarted with the initial wait period.'?

Fullscreen serial-terminal-2023-12-15T092634.902Z.txt Download

*** Booting Zephyr OS build v3.2.99-ncs2 ***
Attempting to boot slot 0.
Attempting to boot from address 0x8200.
Verifying signature against key 0.
Hash: 0x6a...5a
Firmware signature verified.
Firmware version 1
*** Booting Zephyr OS build v3.2.99-ncs2 ***
I: Starting bootloader
I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: none
I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: none
I: Bootloader chainload address offset: 0x28000
[00:00:00.490,783] <inf> nrf_modem_lib_trace: Trace thread ready
[00:00:00.498,474] <inf> nrf_modem_lib_trace: Trace level override: 2
*** Booting Zephyr OS build v3.2.99-ncs2 ***
[00:00:00.499,298] <inf> app_event_manager: APP_EVT_START
[00:00:00.500,396] <inf> app_event_manager: MODEM_EVT_INITIALIZED
[00:00:00.576,354] <inf> app_event_manager: MODEM_EVT_LTE_CONNECTING
%CESQ: 39,1,9,1
%MDMEV: RESET LOOP
+CEREG: 2,"7B0D","000A150C",7
[00:00:01.527,801] <inf> app_event_manager: DATA_EVT_CONFIG_INIT
[00:00:01.867,523] <wrn> modem_module: The modem has detected a reset loop. LTE network attach is now restricted for the next 30 minutes. Power-cycle the
device to circumvent this restriction.
[00:00:01.871,337] <inf> app_event_manager: MODEM_EVT_LTE_CELL_UPDATE
%CESQ: 41,2,14,2
%CESQ: 46,2,18,2

[Øyvind]

What happens if you power-cycle the device?

[Øyvind]

Also, if that does not help. Could you try programming the AT Client sample and issue the following commands:

AT%XFACTORYRESET=0
AT+CMEE=1
AT+CNEC=24
AT+CEREG=5
AT%CESQ=1
AT%MDMEV=1
AT+CSCON=1
AT%XSIM=1
AT+CFUN=1
Skjul

[ralphvn]

It does not help, you just have to wait for 30 minutes I think, after that it starts working again, but if I reset the device too much I think it is in this RESET LOOP again.

Like my last question;

In the attachment you can see the Asset Tracker has the same problem with the RESET LOOP. It says 'Power-cycle the device to circumvent this restriction.' but the documentation you send says 'When the reset count reaches the limit, the blocking restriction is written to Non-volatile Memory (NVM). The wait time cannot be bypassed after the wait has started. If the modem is reset during the wait period, the wait period is restarted with the initial wait period.'?

I think the last is correct and the first not, so I do not think you can circumvent it?

[ralphvn]

Just waiting for half an hour solves the problem.