Solve Wi-Fi problems with Wireless Diagnostics for macOS

Posted: July 26, 2018

Wireless networks are brilliant - when they work. Mostly they do work perfectly well, but there are occasions where something isn't right and you have a poor connection or none at all. What can you do?

If you cannot get on the internet or if you cannot even get on the local Wi-Fi network, determining what is wrong is not easy, but if you are struggling to diagnose the cause of a wireless networking problem, there is a secret utility buried in macOS that can help.

It can analyse the Mac's configuration and the network settings, and then offer advice and help on how to solve the problem. It might not be useful in every situation, in fact, sometimes it can be wrong, but it is still a tool you should try.

Extended Wi-Fi menu

The best place to start when trying to solve networking problems is the Wi-Fi icon in the menu bar at the top of the screen. Do not just click it though, hold down the Option key on the keyboard and then click it. This displays a lot of hidden options and information that are not normally revealed. Here is an example of the sort of information you can see on this menu:

Notice that you can see useful information like the IP address of the Mac and the IP address of the router. If you need to access the router to check or change settings, type those four numbers into a browser's address box.

type of network is shown as PHY Mode and this is 802.11n. Wi-Fi networkds use channels and this one is using channel 3 at 2.4 GHz. The security is shown, WPA/WPA2 and the transmit rate is the network speed, 59 Mbps in this case. The higher numbers indicate faster internet and quicker download speeds.

Restarting the router can sometimes help and modern models check if there are other networks using the same channel and they switch to another one that isn't so crowded. Try restarting the router and see if if shows a new channel in this hidden menu.

The channel number can be changed in the router settings and manually selecting a different one might solve wireless and internet problems because sometimes auto-selection isn't so good.

Open Wireless Diagnostics

Near the top of the extended Wi-Fi menu is Open Wireless Diagnostics. This is a handy tool that can help with Wi-Fi network problems. Click it and keep clicking the Continue button until it starts analysing. It might take a minute or two to complete.

It asks questions like, 'Where is the router located?' and 'What is the make and model of the router?' You don't have to enter any information, but it is helpful if you can.

Wireless Diagnostics report

When it has finished analysing the Mac and the network, the Wireless Diagnostics app shows a summary. In this example there are four items:

At the right-hand side of each of the topics in the summary is a blue i button. Click it and the app shows more information about the problem. Clicking the Custom DNS Settings question mark above shows this:

It reveals that the default DNS settings supplied by the router are not being used and that this might be causing a problem. It then goes on to provide a step-by-step guide to fixing this. There are good reasons for using alternative DNS server settings, but if you are using them it might help to try the default settings just to eliminate this as a cause of your internet difficulties.

A nearby network conflicts with my country code? It seems that one of my neighbours has their wireless router set to DE, Germany. That's weird. Do they know? Should I tell them?

The information provided by Wireless Diagnostics can sometimes be useful if you aren't sure what might be causing a network problem. Run it and see what it says the next time your Wi-Fi isn't working properly. It is a good place to start when troubleshooting but you will probably need to investigate further. Here are some related articles that can help.

Author:

Roland Wadddilove

Tags:

Apple apps