Air Bag On-off Switch problems of the 2008 BMW Z4

¿the vehicle was purchased used from a dealer in October 2012, with about 30600 miles;, current mileage is about 57400. The airbag disabled light in instrument cluster started acting up several months ago; now it is on at all times, whether or not a passenger is in the seat or the car is in motion or stopped. A scan of the vehicle shows a defective passenger occupancy sensor / mat. Resetting the light with the scan tool does not fix the problem. Many 2008 BMW models were recalled for a similar problem, but not the Z4, even though there are several complaints listed here. The local BMW dealer wants $152. 00 shop diagnosis fee and a replacement mat switch could be $1800. 00. This is a safety issue known by the manufacturer from the beginning and should be included in the recall.