The parking brake failed with an amber indicator showing on the dashboard when starting the car. had to put the car in gear (6sp) and then get out and chock the wheels in order to keep the vehicle from rolling down hill. independant repair station informed me there was an error code - 6017 wheel speed sensor dfa_emf in the parking brake module. this error is in fact a bug in the software and required a new verion of code to be loaded at the bmw dealer for a cost of $430. bmw has been aware of this problem since at least 2013 and has not issued a notice or recall. this issue affecting hundreds of bmws needs to be invesigated due to the obvious saftey concerns.