I will check with my service adviser on Monday, I KNOW he knows. I think it's a sequence of switching the ignition on and off and latching the seat belt 5 times. But, again, I'll ask him on Monday and get back to you.

 

For chime only:
Sit in vehicle, passenger seat empty. Start car, with seatbelt light on, latch seat belt, when light goes out, unlatch. When light comes back on, latch belt, repeat this 8 times, you will get confirmation chime. To reenable, repeat procedure. This is for the chime only, not the light. After much debating and legal consul, it has been determined that the chime disable is not a matter of legality, the light would be.

 

This is a great thing to disable. On my BMW 6 series the chime is so so annoying it will just not cease.
I have a few cars and a large drive and move the cars around quite a bit so this incessant binging and bonging is real pain. I think the words Nanny and State come to mind