Signed my paper work for my new c4, started the car and the airbag light lit up. It's been back and forth to the dealer now 3 times always with same result. They have replaced a passenger seat air bag and the airbag control unit and tested all the wiring. The mechanic has no idea where to go next. Has anyone else experienced this. He stated something to the effect of replacing the entire wiring harness in the vehicle. Help, the service department has more miles on the vehicle than I do.