Side/window Air Bag problems of the 2010 Mini Cooper S

The passenger airbag off light comes on with a passenger in the car. The light comes on and remains on at random intervals. I brought the car to the only Mini dealer in colorado and they told me that they couldn't duplicate the fault and that there wasn't a fault code in the computer. I asked to speak to the service manager and he told me that this was normal and that my 130 lb. Wife didn't weigh enough to warrant the srs system in the car.