What does this button do??
 

I have read through the posts and seen no reference to this button. In the manual posted it has no writing on it but in this pic it does - anyone know? Any ideas?

It's "Auto H" button for (de)activating Auto Hold (aka Automatic Parking Brake ) function of electronic parking brake (=EPB).

When activated the EPB is engaged everytime the car stops (even when shifter is in N, D or M/S position), and is released immediately when accelerator is pushed.

When Auto hold function is deactivated you can manually engage - disengage the EPB by pushing "(P)" (Parking Brake) button / lever which is located just above Auto H one.

Thnaks for the quick reply. Is this a standard option or optional? In this picture there is no writing on the button.