It would seem that voice control needs to be activated before it can be used – usually at great expense a bmw dealer. Alternatively a handy bit of software that will do the same is Navcoder – costs about £25. This software can also switch on / alter other settings on the tv, radio, sat nav and telephone modules.
It needs an IBUS Interface to connect your laptop with the navcoder software to the ibus system on the car. See separate post at ……
NavCoder is a Windows application to reprogram BMW navigation computers and other ibus devices. Its written in VB6, and was started in 2006. It has grown much over the last few years, and was last updated in December 2017, over 10 years since the initial release!. It is still actively supported by the author. Here’s what the current NavCoder window looks like (this is the new v3 version, with hugely improved user interface):
More info at …… http://www.navcoder.com/