Bluetooth can be enabled/disabled in SteamVR from Settings > General > Enable Bluetooth communication.

On the same page, there is a button for installing Bluetooth drivers.

If your base stations are not utilizing power management settings or cannot enter standby, you might need to re-install the Bluetooth driver.

1. Deactivate the Bluetooth communication from SteamVR Settings. To do this. go to Settings > General > Uncheck "Enable Bluetooth communication."
2. Power cycle both lighthouses and the link box. Remove the power cable from the back of the link box to ensure that it has been fully cycled.
3. Reactivate the Bluetooth communication in the SteamVR settings.

If that did not resolve your issue, then do the following.

1. Deactivate the Bluetooth communication from SteamVR > Settings.
2. Manually install the Bluetooth driver. You can run the installer manually from: /Steam/steamapps/common/SteamVR/tools/lighthouse/bin/win64/vivebtdriver.exe
3. Repeat the steps from above to power cycle and re-enable Bluetooth communication, then test the issue.