TRM250 No Service

Hi Guys,

I hope you can help. I have recently purchased 2x TRN250 modems.
I dutifully downloaded the driver and installed it on to a Windows 11 PC.
I placed the SIM from my mobile phone (Which works perfectly) into one of the units.
The logo of my service provider is displayed when I select the mobile connection, but, it states there is “No Service”. I tried inputting the APN detail from my service provider, but, this made no difference.
I have tried the Ping 8.8.8.8 and get destination host unreachable. Any ideas.
How can I get the unit to connect ?
I’ve tried to connect to the Web UI but I can’t seem to get into it.

Thanks in advance for the help.

Hello,

TRM devices can only be controlled using AT commands, so it’s hard to say what could be wrong when Windows are controlling the modem. Here are a few resources which could be helpful when troubleshooting the issue:
https://wiki.teltonika-networks.com/view/Setting_up_mobile_interface_on_raspberry_pi
https://wiki.teltonika-networks.com/view/TRM240_AT_Commands
Make sure that:

  • The PIN is entered (if needed);

  • Correct APN and MBN are selected;

  • CFUN is set to 1;

If the provided resources do not help, please attach the output of the following commands:

AT+CFUN?
AT+CREG?
AT+QNWINFO
AT+CGREG?

Best regards,

Thanks for the quick response.
That makes sense why I can’t access the WEB UI.

As far as I know there is no pin set.

I have selected the correct APN, not sure what you mean about MBN.

OK the responses:

AT+FUN?
+CFUN: 1
OK

AT+CREG?
+CREG: 0,2
OK

AR+QNWINFO
+QNWINFO: “CAT-M1”, “5051”,“LTE BAND 28”,9410
OK

AT+CREG?
+CREG: 0,4

OK

Hello,

Thank you for the output.
A few more commands to run:

AT+CEREG?
AT+CGREG?
AT+CPIN?

Best regards,

OK here they are…

AT+CEREG?
+CEREG: 0,2
OK

AT+CGREG?
+CGREG: 0,4
OK

AT+CPIN?
+CPIN: READY
OK

Any ideas?

Hello,

Could you try checking different SIM cards? What about different machines that the TRM250 is connected to? Perhaps it would be possible to check it with a Linux machine to see how the modemmanager handles it?

Best regards,

Hi,

I’m still struggling to get anything out of these modems.
I have tried a Windows 11 PC, Windows 7 PC, and an industrial tablet running Windows 7.
I have tried 2 different SIMs out of working mobile phones. I can see the SIM is recognised but there is no internet connection.
I’m assuming all the setting you asked me to provide data for were OK?
I think I need you to walk me through the set up, because I’m obviously missing something.

I don’t have access to a Linux machine.

The two different SIM cards were from different suppliers.

NO further advice?

Hello,

The only thing I can say, is that the device is not able to find the operator, and CGREG status is 4 (Unknown). Since the device is fully managed by Windows, I’m not sure of the commands that are being executed / the operator support for this technology in your region.
You could try running AT+CGATT=1, however, as the device cannot even register onto the network, I doubt that it will help. I’d also recommend contacting your carrier and checking with them if they are not blocking the device from their side.
Finally, make sure you have all of the necessary drivers installed from here: TRM250 Downloads - Teltonika Networks Wiki

Best regards,

Very strange.
I tried the AT+CGATT=1 and it gave no response.
The sims I have used have been put into different mobile phones, Surveying hand controller and other mobile based equipment without issue.
My confusion is every sim I put in the units behave the same “No Service” although the logo of the provider is displayed. My plan was to put in a big order if these units worked.
Unless you can give me any further pearls of wisdom, at this stage I can’t continue with your product.

Hello,

Are you sure your carrier and the mobile plan supports NB-IoT / Cat M1 / EDGE networks?
For any further troubleshooting, additional sensitive information is needed. Please reach out to your designated sales manager, reseller, or fill out the Contact Us form here: Teltonika Networks - LTE Routers, Gateways & Modems for IoT

EDIT: Please also run the following command: AT+COPS?

Best regards,

OK here’s the result of the request:

AT+COPS?
+COPS: 0

OK

Are you sure your carrier and the mobile plan supports NB-IoT / Cat M1 / EDGE networks?

I’m beginning to think it doesn’t, it not backwards compatible?

I have filled out the requested document.

Apologies, I’ve provided the wrong command, try this: AT+COPS=?
It will give the status of each available operator, and indication if the device can connect to it.

EDGE should be, but the other technologies are not.

Best regards,

OK

AT+COPS=?
+COPS: (3,Telstra Mobile",“Telstra”,“50501”,8),(0,1,2,3,4),(0,1,2)

OK

Strange that it shows Telstra as my provider is TPG

The output is showing Telstra network, as it’s the only compatible network found nearby. However, it’s status is 3, meaning it’s forbidden. This is most likely because TPG does not have roaming agreements in place with Telstra. So if you wish to use LPWAN technology in your current location, I’d recommend considering moving to Telstra.
Alternatively, TRM240 is another great alternative, as it uses standard LTE/3G/2G implementations and works on the same frequency bands as your mobile phone.

Best regards,