Question

I have a RUT-955 which worked perfectly with my SIM-Card in Spain for weeks. Now we are back on the road and the mobile network just won't connect. The error reaches from SIM (N/A) to SIM (not inserted) to connection to internal modem failed. I did factory reset for troubleshooting but to no avail. The firmware versions are:

RUT9_R_00.07.04.3

SLM750_4.0.6_EQ101

Is there anything I can do to get the device working? We are travelling right now and I urgently need this for my work.

I tried the modem updater as well with the following result:

root@RUT950:~# modem_updater -g
[INFO] Detected modem_n: 0
Modem List:
Command failed: Request timed out
[0] Meiglink SLM750-VE | USB_ID: 1-1 | Firmware:  | builtin:true
Command failed: Request timed out
[ERROR] modem_n is wrong or modem is not responding.

Answer 1

Hello,

Based on the logs, it appears that there are continuous modem timeouts, leading to the unavailability of modem details, including cellular information. So it is hard to say what causes this.

Could you please check if you have enabled roaming? You can find this option in Network -> Mobile -> General.

Does your phone work fine with this SIM while you are roaming? If so, can you check the APN settings on your phone when you use this SIM? Then, try configuring the router to use the same APN.

Your operator may provide a specific APN for roaming. APN can be configured in Network -> Interfaces -> Edit mob1s1a1 (SIM1). There, you can disable auto APN and enter your custom APN.

Have you tried using a second SIM slot?

Also, have you tried a different SIM card, preferably from a different operator, to see if it works?

Kind Regards,

Andzej

Comments

Thanks for the feedback.

• SIM works fine in my mobile and has worked fine before inside the RUT
• Roaming is enabled
• APN has been set manually and on auto (no difference)
• Tried second SIM-slot (no difference)
• Added some tape to the back of the SIM (no difference)

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Update: after a very long wait, slot 2 seems to have start working...

Do you still recommend to run the modem_updater?

---

Hello,

If the connection is currently working, could you provide another troubleshooting file? This file may contain more information than the previous one since during the generation of the first troubleshoot file the modem was unresponsive and the file lacked cellular information as a result.

Could you please check whether slot 1 is functioning properly now?

If the problem persists and the modem's firmware is outdated, it might be worth considering an update. However, let's check the new troubleshoot file first.

Kind Regards,

Andzej

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Hi Andyej, uploaded another file. Regards.

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Hi,

I have sent you a private message.

Kind Regards,

Answer 2

I moved the tray to slot 1 but it is not working. attached the troubleshoot file.

also lan 1 seems to have stopped working (so it seems, tried different cables and adapters, all working fine in 2 and 3).

https://community.teltonika-networks.com/?qa=blob&qa_blobid=1828013617731576258

Comments

Hello,

  

The troubleshoot file was generated right after the device was booted, thus it was not connected to a mobile network at the time. Please wait at least a few minutes after the device boots up and generate another troubleshoot file. Thank you.

As for LAN1, when generating a troubleshoot file, make sure you have some device  plugged into the LAN1 port. This will give us some more insight into what the issue could be.

  

Best regards,
DaumantasG

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No, the device was left with the SIM in the slot for 15-30 minutes before I made the file. But you might remember that this was the original issue (SIM not working in slot 1).

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Sorry, there was a surprisingly small amount of logs present.

I can see that SIM 2 is set as the default SIM, so SIM1 will not be able to establish the connection. Please change the default SIM in the Network → Mobile → General section, by enabling the "Default SIM" option in the SIM1 tab and pressing Save & Apply.

Please keep in mind, that only one SIM card can be active on RUT955 at the same time.

  

Best regards,
DaumantasG

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Now lan 1 and sim slot 1 works... I honestly don't know that to make of all this... maybe the tape on the back of the sim-card was enough?

still no modem update to make sure?

https://community.teltonika-networks.com/?qa=blob&qa_blobid=11662904131767596131

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Perhaps it could be the tape if the SIM contacts are worn out.

As for the modem_updater, I would advise against it, as I doubt it will change the behavior, and it also runs some risks of bricking the integrated modem.

  

Best regards,
DaumantasG