Air Bag Not Deploy problems of the 2007 BMW Z4

'airbags have never been deployed according to carfax history. I was commuting home, waiting at a stop light, when I heard a very loud pop. At first, I thought something had fallen on to my car because the dash did not explode. Reveraling the airbag. I started to smell smoke coming from the passenger side and noticed that the airbag light was on. I wasn't able to start the car given the battery safety terminal disengaged. I am lucky that the driver side airbag didn't deploy, or even deploy while I was driving.