I have a Logitech MX Keys keyboard, a 2018 MBP running Mojave, and an OWC Thunderbolt 3 dock. The keyboard is connected through USB C to the dock.
If I had the keyboard working and then unplugged the mac from the dock, when I plug it back in, it works fine. UNLESS I had opened the laptop and used the built-in keyboard in the meantime. Then when I plug it in, the keyboard does a slow flash and the mac shows no evidence that it can connect.
Some arbitrary, looong amount of time later, maybe 20-30 minutes, it finally gets around to connecting, taking no action on my part as far as I can tell. Attempting to manually pairing it in the bluetooth settings doesn't do anything, nor does pressing the button to connect on the keyboard (referring to the source-1, source-2, source-3 buttons to the right of the F-keys). The keyboard has only ever been used with this machine.
My guess is that it's only connecting through Bluetooth. Is it not designed to actually be able to connect through USB-C to the computer itself? Like, is that cord JUST for power? That feels like a pretty moronic design choice. But if that's so, is there anything I need to do to make the keyboard reconnect quickly and automatically?
Best Answer
The Logitech MX Keys is a wireless keyboard that uses either Bluetooth LE (low energy) or the Logitech Unifying wireless receiver. The USB cable is for charging only.
So, excluding the USB connection from your question, this comes down to the following possibilities:
You might have interference issues with your BT (AirPort card) on your Mac. To isolate, remove the dock and try pairing. If that doesn’t work, try pairing with the USB receiver. But to get a solid diagnosis of your BT adapter, try a different device to ensure it connects as it should
As for your keyboard, try pairing with another computer. If the symptoms persist, it’s the keyboard and it should be returned. If they don’t, then you’ve definitely narrowed it down to your Mac.