One problem related to air bag not deploy has been reported for the 2011 BMW 335. The most recently reported issues are listed below.
I have a passenger restraint system fault affecting airbag, belt tensioner. My car has sport seats that have been recalled in a previous campaign due to the seat mat sensor failure. My car was not included in the recall. BMW quoted me a replacement seat mat using the same recalled product from 2013 and 2006. My car currently has a seat belt malfunction code and the seat mat sensor is defective. This went defective at 84,000 miles on the car. As a result, the airbags will not deploy in a crash because the seat does not detect an occupant with the seat belt malfunction!.