4G LTE CellSpot issues

Troubleshoot 4G LTE CellSpot issues.



Preliminary checks

  1. Follow 4G LTE CellSpot setup.
  2. Ensure at least 2 hours has passed since setup.
  3. Confirm you have high-speed Internet with at least the speeds listed below. If unsure, run a speed test to determine if your Internet service provider (ISP) supports those speeds.
    • Ping/latency: 200 ms (or less)
    • Upload: 0.5 Mbps (or more)
    • Download: 2 Mbps (or more)



No signal, blinking green light, did not complete setup

  1. Re-position GPS antenna as close to the window if possible to reduce the 911 location identification time. Ensure 4G LTE CellSpot is not in direct sunlight, as it can cause a disabling error.
  2. Are you using multiple routers? If Yes, ensure 4G LTE CellSpot is plugged directly into the modem/router combo unit and not your secondary router.
  3. Stop using programs that use a lot bandwidth like video streaming, to speed the download of the latest software from the T-Mobile network.
  4. Unplug the 4G LTE CellSpot.
  5. Turn off your modem/router combo unit and router.
  6. Turn on your modem/router combo unit first, and then any other routers.
  7. Turn the 4G LTE CellSpot on and restart the installation.
  8. On the modem or modem/router combo unit:
    • Open ports: UDP 123, UDP 500, UDP 4500. Some ISPs charge to open ports.
    • Verify bridge mode is enabled. It can help troubleshoot problems. Contact your ISP or search online for steps. Bridge mode may turn off the Wi-Fi function of the bridged router. If bridge mode turns off Wi-Fi with a T-Mobile Wi-Fi CellSpot Router, contact us.
    • Contact your ISP, IT department, or equipment manufacturer for help with these settings. T-Mobile can't provide detailed help with non-T-Mobile services or equipment.
  9. If all troubleshooting has been completed and the issue continues, contact us.



Calls, messaging, or data problems after setup

  1. Verify Wi-Fi Calling is disabled on your connecting devices.
  2. Turn off the device, and then turn it back on.
  3. Check if the issue is happening only on the 4G LTE CellSpot or also on Wi-Fi Calling and/or the T-Mobile network. If happening on T-Mobile network or Wi-Fi Calling, it is not a CellSpot problem. Follow appropriate troubleshooting for the T-Mobile network.
  4. Verify LED status. Follow 4G LTE CellSpot status lights to make any device adjustments.
  5. If all troubleshooting has been completed and the issue continues, contact us.