What is this button for?

[xsi123]

It looks like this is available only on the xDrive model. Any idea?

[richschneid]

I think it may be hill descent control.

[mzwicker]

You got it that what my CA told me.

[BimmerUKF10]

Can't get xDrive in the UK (wish we could!), but that looks like the parking sensors button??

[pharding]

In the US. Depending your option packages it turns on Park Distance Control alone OR Park Distance Control and Parking Asssistant for automatic parallel parking.