One problem related to air bag not deploy has been reported for the 2013 BMW 528. The most recently reported issues are listed below.
A vehicle(SUV) ended my car in the rear in a pretty good speed when I was in the slow traffic almost stationary(5 mph). Crash impact was high. Had to call in an ambulance as my friend sitting in passenger seat was hurt badly. As we realize after the crash, engine got stopped & airbags failed to deploy due to fault in airbag. Engine did not start later & the car was towed to a facility in prospects heights. This happened on a city highway when driving in a straight lane. Very light snow showers at that time around 6pm on 02/26.