Multiple Magic Mouses won't connect to Bluetooth

Ok, let's try resetting the Bluetooth module on your Mac by using the following command in the Terminal app:

• sudo pkill bluetoothd

Then restart your Mac.

If that doesn't help, there's a possibility the internal Bluetooth chip (part of your Broadcom Wi-Fi/BT combo module) has failed or its USB bus is flaky. You could check Console.app for any USB or Bluetooth-related errors on boot or device connection attempts ...

... and if that doesn't find anything, then your last step is to contact Apple Support directly for further assistance with this issue.

Ok, got it. Thanks.

The fact that your Bluetooth address is showing as NULL, the state is Off, and the Bluetooth toggle won’t stay On is a red flag. That generally means the macOS Bluetooth stack either can’t talk to the Bluetooth chipset, or that the chipset itself isn’t being recognized/initialized properly.

Since the Bluetooth controller is a USB-attached internal device (as per the “Transport: USB” line), a reset of system-level functions may help.

Reset NVRAM

1. Shut down the Mac.
2. Power on and immediately hold Option + Command + P + R.
3. Hold keys for 20 seconds, then release.

Reset SMC (for iMacs without T2 chip)

1. Shut down the iMac.
2. Unplug the power cable from the back.
3. Wait 15–20 seconds.
4. Plug the cable back in, wait another 5 seconds, then turn it on.
5. After the reset, try toggling Bluetooth back on and see if the controller shows a proper address and the toggle stays enabled.

Are you trying to use the new USB-C Apple Magic Mouse with your iMac? If so, the issue is mostly that it requires macOS Sequoia 15.1 or newer to fully operate.