NR/FWA Series [5G] - Connection Issue Troubleshooting Guide

Created April 19, 2023 11:00 - Updated July 14, 2023 14:18

Serhii Boiarynov

This article will show how to fix connectivity issues, disconnections and if the device cannot connect to internet, cannot find SIM-card. For NR7101, NR5101, FWA510, FWA710.

This is a follow-up article to these articles:

1) NR/5G-Series - Basic Troubleshooting

2) NR/FWA Series - Advanced Troubleshooting [5G Routers]

1) NR7101 doesn’t connect to the network

Please follow the steps below to check the settings and Installation first.

1.1 Align the NR7101 to the base station

Please refer to the signal coverage map:
https://www.nperf.com/en/map/

Ensure the NR7101 is under the coverage of the signals.

1.2 Check the SIM status and check if SIM card is locked.

On GUI, go to Menu > System Monitor > Cellular WAN Status.

On console, use the command: cfg cellwan_sim get to check if
information can be retrieved correctly from the SIM card.

1.3 If your SIM card isn't recognized

Here's a step-by-step guide on what to do when a Zyxel 5G router cannot recognize the SIM card:

Check the SIM card insertion: Ensure that the SIM card is inserted correctly into the SIM slot of the 5G router. Sometimes, a loose or improperly inserted SIM card can prevent the router from recognizing it. Carefully remove and reinsert the SIM card, ensuring it is properly seated in the designated slot.
Test with a known working SIM card: If you have access to a mobile phone with a working SIM card, try inserting that SIM card into the 5G router. This step will help determine whether the issue lies with the SIM card or the router itself. If the router recognizes the mobile phone SIM card, it suggests that there may be an issue with your original SIM card.
Verify the plastic cover (for outdoor routers): If you are troubleshooting an outdoor 5G router, ensure that the plastic cover is properly placed over the device's connectors, including the SIM slot. This cover protects the router from environmental factors such as dust, moisture, or physical damage. Improperly placed or missing plastic covers can potentially interfere with the router's ability to recognize the SIM card.
Contact Zyxel support: If the previous steps did not resolve the issue, it is recommended to reach out to the Zyxel support team for further assistance. They have the expertise and resources to help troubleshoot and provide specific guidance based on your router model and the nature of the problem. Contact Zyxel's customer support through their website, email, or phone to report the SIM recognition issue and seek their guidance.

Remember, Zyxel's support team is dedicated to assisting customers and can provide more detailed troubleshooting steps or escalate the issue if necessary.

3. Check the APN profile

On GUI, go to Menu > Network Setting > Broadband > Cellular APN.

On console, use the command cfg cellwan_mapn get to check the
settings of the APN profile are correct.

4. Check Band and Access Technology settings

On GUI, go to Menu > Network Setting > Broadband > Cellular Band.

On console, use the command cfg cellwan_band get to check the
settings of the Band and Access Technology are correct.

5. Check the Data Roaming settings

On GUI, go to Menu > Network Setting > Broadband > Cellular WAN.

On console, use the command cfg cellwan get to check the settings of
Data Roaming.

6. Check Cellular PLMN

After you adjust the settings but there is still no connection, check the
network visibility and then choose the network to check the connection.

On GUI, go to Menu > Network Setting > Broadband > Cellular PLMN.

Disable PLMN Auto Selection and press the Scan button to get the list.

Note. After the action, it will cause a network disconnection. Your SSH session might be terminated and you
need to log in via SSH again.

Manually select a network to connect. And after confirming that all the settings and installations are correct but the problem still persists, please proceed to the next step.

2) Collecting information

Please provide the following information to Zyxel when reporting an issue
1. Firmware version
2. Issue description and your troubleshooting steps with the results
3. A remote session with at least 50 GB of hard drive space is needed for CSO to capture the necessary logs

2.1 Preparation in the remote session

2.1.1 Ensure that NR7101 is in Routing mode before capturing the logs.

On GUI, go to Menu > Network Setting > Broadband > Cellular APN.
Modify the first entity to disable IP Passthrough function.
If you use two SIM cards, you need to configure the first entity for both
cards.