Bluetooth is what your Mac uses to connect to wireless devices like keyboards, mice, trackpads, speakers, and other peripherals. Generally, it's a reliable technology. At some point however, the chances are you'll run into difficulty establishing a Bluetooth connection with one or more of your devices.
Most problems can be fixed by unpairing and repairing the Bluetooth device, changing its batteries, rebooting your Mac, or performing an SMC reset. But if none of these methods work, you can always try resetting your Mac's Bluetooth module. Here's how to do it in macOS using the hidden Bluetooth Debug menu.
How to Reset Your Mac's Bluetooth Module
Before proceeding, bear in mind that if your setup relies exclusively on Bluetooth for communicating with your keyboard and mouse, then you're going to temporarily lose connection to them using the following methods, so you might want to have a backup wired input device option just in case.
- Holding the Shift + Option (Alt) keys on your Mac's keyboard, click the Bluetooth symbol in the top-right corner of the macOS menu bar. (If you don't see it there, you need to check Show Bluetooth in menu bar in System Preferences -> Bluetooth.)
- Locate the revealed Debug submenu and hover your mouse cursor over it.
- Click Reset the Bluetooth module.
- Now, restart your Mac.
You'll notice a couple of other potentially useful options in the Debug submenu. Factory reset all connected Apple devices does exactly what it says – forces any Apple-branded Bluetooth accessories back to the default settings they came with out of the box. It's a reliable fallback option if you've tried everything else to fix a connection issue, including resetting the Bluetooth module.
Lastly, the Remove all devices option might prove useful if you're moving your Bluetooth mouse and keyboard to another Mac, for example. However, you can also remove devices on an individual basis from the macOS menu bar, as long as you hold down Shift + Option (Alt) before you click the Bluetooth symbol.
Removing devices in this manner means you're not also banishing a whole bunch of other established Bluetooth connections like speakers and so on that you might want to keep.