To activate bluetooth connectivity on your Nokia Bluetooth Stereo Headset BH-905, press and hold the multifunction key for about 2 seconds. The headset beeps, and the Bluetooth indicator light briefly flashes green.

The headset tries to connect to the last used mobile device that supports the HFP Bluetooth profile and the  last used music player that supports the A2DP profile, if the same device does not support both profiles.When the headset is connected to the device and is ready for use, the bluetooth indicator light flashes blue slowly. If the headset has not been previously paired with any device, it automatically enters pairing mode.

To deactivate bluetooth connectivity on your Nokia Bluetooth Stereo Headset BH-905, press and hold the multifunction key for about 5 seconds. The headset beeps, and the Bluetooth indicator light briefly flashes red.

If the headset is not connected to a Bluetooth device within about 30 minutes, the headset deactivates bluetooth  connectivity automatically. Bluetooth connectivity is also deactivated if you connect the CA-143U audio cable to the headset.