Passenger airbag off light is on, have to replace seatbelt receptacle $450

We call them stealerships because they're going to rob you $450 for a part you can get at your local auto wrecker for $25 and then odds are when it doesn't fix they're going to find the most common cause, which is damage to the wires under the seat that you can easily repair with some wire crimps, but they'll add another $700 to your bill to "replace wiring harness" because they aren't allowed to patch, only replace with new.

 

The OCS calibration is something you can in principle do if you have a good-enough scan tool and a 30 kg (66.1 lb) solid metal weight to place on the seat (they say to avoid other kinds of weight like water-filled). If you don't have that stuff handy, it's easier for the dealer.

I'm not positive whether you need the weight for the calibration procedure itself, or only for the sensitivity check after.

 

That's normal in my car; unless someone is sitting there. If someone is sitting there the lamp should turn-off and the seat belt chime should activate.
Not sure how it works on your gen3; but that's how it works on a gen4.......

Hope this helps....