Mr. B. I don't think it can be done. You can have the passenger air bag turned off by unplugging it but then you have to recode it anyway to accept that. To turn it back on you have to recode the module..
I ran into this recently on a customers 540it with rear side bags turned off that he had reconnected, we could clear the error codes but as soon as you started the car it came up again with some really wrong error messages since it was now reading more bags than it knew of in the system.. Had to have the system recoded to accept the side airbags again.