Use the router tool to test 4G internet connections.
We can use the pre-built tools and web terminal to test the internet connection. After login router admin panel, go to "Network > Diagnostics."
Use the "Ping" tool to ping a public DNS server or website to test latency. If returning a "Bad address" error, the internet connection is not working. If ping results have high latency, such as larger than 300ms, the Internet speed is not fast.