Bluetooth issues can be troubleshooted in several ways. The first thing to check is toggling airplane mode which will sometimes get Bluetooth functioning again. Next, make sure Bluetooth is enabled in the top bar, or in the Bluetooth system settings.
Then, try reinstalling Bluetooth related software with this command:
sudo apt install --reinstall bluez gnome-bluetooth indicator-bluetooth pulseaudio-module-bluetooth
There is a program called ‘Bluetooth Manager’ which is included with XFCE. It can sometimes pair and trust Bluetooth devices better than the default Bluetooth settings. Install it with:
sudo apt install blueman
Then, run Bluetooth Manager. Check for the device being trusted, and also try re-pairing in that program.
lsmod | grep Bluetooth dmesg | grep Bluetooth
These will show if the Bluetooth module (driver) is loaded, and what the system messages are.
sudo systemctl status bluetooth
This will check to see if the service that handles Bluetooth is running.
rfkill list sudo rfkill unblock bluetooth
This will check to see Bluetooth is blocked, and if so, unblock it.
pactl load-module module-bluetooth-discover
This will load the PulseAudio module responsible for Bluetooth Audio. Typically, it’s loaded by default, but sometimes a manual loading can get Bluetooth headsets working again.
This will show all Bluetooth related messages. Try leaving this command running while pairing or using a device to see any error messages or failures.
Here are a few addition tidbits about the Bluetooth system that may help with troubleshooting.
Occasionally the kernel and/or Linux firmware will have problems. Sometimes, newer Linux firmware packages will have fixed bugs that aren’t yet in the Ubuntu repositories. They can be downloaded from here:
Then they can be installed with this command:
sudo dpkg -i linux-firmware_1.164.1_all.deb
Sometimes, additional programs need installed for mobile equipment file transfer. Please install the transfer tool with this command:
sudo apt install obexfs obexftp
Then connect (pair) to the device and see if send files works. To receive files over Bluetooth you will need to enable the option in Personal File Sharing.