Old topic I know, but the Emergency brake caught me unawares yesterday.
I had just backed out of our garage, but my neighbours had done the same and blocked me from driving forward. Their daughter had nipped back into their house so I sat patiently waiting for their vehicle to move.
I crept forward at about 1-2 mph but still several metres away, when all of a sudden, my car slammed its brakes on and the Red 'Emergency brake now ' (or whatever it says) lit up on the dashboard.
I can only surmise, at the time, I think the young girl was running back to the neighbours car, and the sensors had detected 'an obstruction'. I was still several metres away doing literally walking pace though, so I guess my car thought it knew best and braked! I think next time, I will just remain stationary!