Bluetooth on the MacBook Air M2 is Bluetooth 5.0, and Apple's pages split the faults into accessories that will not connect, accessories that connect and drop, and headsets that connect but do not work for calls. First make sure Bluetooth is on in System Settings, Bluetooth, using the trackpad or a USB mouse. For a Magic Keyboard, Magic Mouse or Magic Trackpad, Apple's page says to check that the accessory is on and charged, connect it with a Lightning or USB-C cable to the Mac to pair it, and switch it off and on. For a headset, open System Settings, Sound and choose it for both Output and Input, because a Mac can play through the headset but listen on the built-in microphone. Remove the device and pair it again.
The checks in more detail
If it drops, interference from busy 2.4 GHz Wi-Fi or other wireless devices is the usual cause, and Apple has a page on resolving it. The Air's USB-C hubs, if poor, can emit noise near the Bluetooth antenna, so test with the hub unplugged. Restart and update macOS. Option-clicking the Bluetooth icon in the menu bar shows the firmware version and the connected devices' battery levels, which tells you whether a failing accessory is simply flat.
The same menu offers Debug options on older macOS, and in current macOS Apple's pages describe removing a device and pairing again rather than resetting modules. If an older Bluetooth accessory only works up close, its own battery may be weak or it may use an older standard, and replacing the battery or the accessory is cheaper than searching for a Mac fault. Try the accessory on an iPhone as well, since success there clears the Mac of blame.
Differential
Likely causes of “Apple MacBook Air Bluetooth is missing, will not pair or disconnects”, and how to tell them apart
- 1
An accessory off or flat
What separates it It does not appear
How to confirm Charge and switch it on, and pair it by cable
- 2
A headset not chosen for input
What separates it It plays but others cannot hear you
How to confirm System Settings, Sound: choose it for Input and Output
- 3
A stale pairing
What separates it The device shows but will not connect
How to confirm Remove it and pair again
- 4
Interference from a hub or Wi-Fi
What separates it Dropouts
How to confirm Unplug the hub and use 5 GHz Wi-Fi
- 5
A software glitch
What separates it Bluetooth is grayed out
How to confirm Restart and update macOS
Before you touch a setting
Record this first — changing settings destroys the evidence
- The accessory and its battery
- Whether the headset is selected for input and output
- Whether a hub is attached
- The macOS version
Try in this order
0 of 8 completedCheck Bluetooth is on
ReversibleSystem Settings, Bluetooth.
Pair a Magic accessory by cable
ReversibleConnect it with its cable, then disconnect.
Choose the headset in Sound
ReversibleFor both Input and Output.
Remove and pair again
ReversibleIn Bluetooth settings.
Unplug USB hubs
ReversibleTo test for interference.
Restart and update
ReversibleInstall the latest macOS.
Option-click the Bluetooth icon
ReversibleRead each device's battery and status.
Check the accessory's battery
ReversibleA flat accessory fails to connect and looks like a Mac fault.
Model-specific
What is true of this model and not of its siblings
- Two settings
- Output and Input are separate for a headset.
- Hubs
- USB hubs can emit noise near the antenna.
- Battery levels
- The menu shows each accessory's battery.
- Re-pairing
- Removing and adding is Apple's first fix.
Stop boundary
When this stops being a self-service repair
- !If Bluetooth is grayed out after a restart, contact Apple Support
- !If one accessory fails on all devices, contact its maker
- !A hub that disrupts Bluetooth should be replaced
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why does my headset not pick up my voice on a Mac?+
The input may still be the built-in microphone.
How do I pair a Magic Keyboard?+
Connect it by cable first.
Do hubs affect Bluetooth?+
Poor ones can.
Which Bluetooth version does the M2 Air have?+
5.0.
How do I check my keyboard's battery?+
Option-click the Bluetooth icon.
Should I reset Bluetooth modules?+
Re-pair first.