Nordic Thingy 91 LED won´t switch to yellow with 1NCE SIM

[Jackhead]

Hello,

I want to connect my Thingy 91 to the nRF Cloud to use LTE Link Monitor and other features. The provided iBasis SIM card isn´t supported in Germany so I got another SIM from 1NCE which has NB-IoT coverage ( I checked it with this map https://t-map.telekom.de/tmap2/mobileiot).

In the getting started guide there is mentioned that I just have to insert the SIM into the Thingy91 and then I have to wait for the LED to change to yellow but this never happens.
The LED always blinks blue or maybe white, basically the standard color when you switch it on.

The SIM is working. A colleague of mine tried the SIM in an LTE modem and it worked fine. They had to enable roaming and change the APN but the SIM seems to be alright.

Why does the Thingy91 never changes to yellow? 

I updated the firmware and due to a suggestion from an older ticket I run the thingy91_nbiot_legacy_pco_dfu_2020-04-29_bc7ade8b.hex file from the the current zip.-file on your page.

Can you please help me to bring the Thingy91 to life? I hope you have some helpful information for me.

Best regards.

[Martin Lesund]

Hi Jackhead,

I would recommend that you flash the AT client to see what you need to do on your first connection.

E.g. 

#In your case first make sure that the Modem is OFF:
AT+CFUN=4

#change to nb-iot
AT%XSYSTEMMODE=0,1,0,0

# Use legacy PCO
AT%XEPCO=0

# Set the APN correctly 
AT+CGDCONT=0,"IP","iot.1nce.net"

# Set the network notification
AT+CEREG=5

#Turn ON the modem
AT+CFUN=1

#Wait til you get connected and call the XMONITOR commant to see the additional info
AT%XMONITOR?

# Then turn OFF the modem with the following command to store the historical data in the NVS
AT+CFUN=0

# wait for OK and then reflash the device with the nb-iot_legacy application (asset_tracker)

Then you should be able to connect.

Best regards,
Martin L.

[Jackhead]

Hello, I´ve tried your commands but the Thingy still won´t connect.

When I open the LTE Link Monitor and plug the Thingy via USB in my Windows PC the UART is red, Medem is green, UICC is red, LTE is grey and PDN is red. I don´t see any signal strength.The mode is "PS mode 2". 

When I put in AT+CFUN=4 I get this answer: 

AT+CFUN=4%XSIM: 0%CESQ: 255,0,255,0OK

The Modem sign is still green but I think it should have changed to red?

Then I continued with the commands. 

AT%XSYSTEMMODE=0,1,0,0
OK
AT
OK
AT%XEPCO=0
OK
AT+CGDCONT=0,"IP","iot.1nce.net"
OK
AT+CEREG=5
OK
[00:10:00.373,077] [0m<inf> lte_lc: Network connection attempt timed out[0m[00:10:00.388,702] [0m<inf> lte_lc: Using fallback network mode[0m[00:10:00.394,744] [0m<dbg> lte_lc.w_lte_lc_connect: Network mode: AT%XSYSTEMMODE=1,0,1,0[0m
AT+CFUN=1
OK
AT%XMONITOR?
+CME ERROR: 0
AT+CFUN=0
%CESQ: 255,0,255,0
OK

This is the exact expression of the error I get after the AT%XMONITOR? command: Error: AT%XMONITOR? failed: phone failure

Did I execute the steps correctly? The Thingy is running the legacy_pco hex file and the current mwfm. 

Can you see any mistakes?

Best regards