May seem a silly question but if the car has sat overnight and without turning the ignition on, if you removed the airbag in the steering wheel what would cause it to go off, as it can't have any power going it?

The reason i ask is i don't have the code for the radio and really don't want to pay the robbers at audi for getting it for me, unless of course there is another way of getting the code and then i would be happy to disconnect the battery.