One problem related to air bag on-off switch has been reported for the 2010 BMW 328. The most recently reported issues are listed below.
The passenger side "seat mat switch" failed, disabling the srs system. A local BMW dealership replaced the defective part charging me $1264. 20. This vehicle was purchased new by me; was never involved in an accident; had accumulated 48116 miles on the odometer. BMW refused to acknowledge responsibility; however this problem has been reported a number of times to BMW and it did acknowledge prior years' problem with this part and authorized warranty extensions for over 70,000 vehicles.