2012 Subaru Impreza air bags problems

Followed too closely through a double intersection with a non-functioning light. Police officer directed traffic through the intersection but apparently we had to stop before the second intersection. Apparently I slowed down enough that the airbag did not deploy. I indicated 20 but surely my airbag would have deployed at that speed. Was able to drive the car under its own power off the road into a subway parking lot. As I was maneuvering into a parking spot the engine caught on fire.

Usually it should be on, with a passenger sitting in the front passenger seat while driving. But since about 3 months ago, the passenger air bag off indicator light turned on when there was passenger sitting in the car. This.happened about 5-6 times during the last 3 months. We made an appointment and sent the car to garavel subaru dealer in norwalk, ct on 9/5/13 at the milage around 29,000miles. They looked at the car for just 10 minutes and could not find any issue related to this.