Yealink SIP-T46S phone LCD display shows the message No Service. There is no dial tone, and you are unable to make or receive calls.
- In cases where the phone had been properly working for a long time and is only suddenly afflicted with these error messages, power cycling your network is often able to clear it up.
- Next, check if the firmware is up-to-date. Recommended Firmware is 18.104.22.168.
- Check the firmware of the phone by pressing OK.
- Another way to check the version is via the web GUI by obtaining the IP address from the phone or the Client list table from your router.
- Log in to the phone's IP address (default user/password: admin/admin).
- Navigate to Status > Status > Firmware Version.
- If the firmware does not match the recommended you can download the firmware version here.
- Download the T46S(T48S,T42S,T41S)-22.214.171.124.rom file.
- Next, go to Settings > Upgrade > Select and Upgrade Firmware.
- Click Choose File choose the firmware file saved previously, and press Upgrade.
- The phone will reboot and update it's firmware, once done proceed to the next step.
- Make sure to provision the phone to 8x8 server.
- Go to Settings > Auto Provision.
- Enter Server URL: https://ylcfg.8x8.com/yealink/
- Click Autoprovision Now.
- The phone will reboot twice and once booted, will have the chance to activate.
Other helpful network troubleshooting:
- Swap out the Ethernet cord connecting the phone to the network for a different one (to see if a faulty cord might be the issue).
- Is the phone connected to a wall jack? If so, try connecting it directly to a networking device (router or switch).
- If the phone is connected to a networking device, try plugging it into a different port on the device (to see if a faulty port is the issue).
- If accessible, review the firewall/router settings and be sure to disable the following:
- Try setting a static IP on the phone, which has been known to help resolve these issues.
- Phone has an Outdated firmware.
- Phone is unable to successfully register a SIP account with our services.