My car freaked me out on Friday and I'm hoping you guys can guide me on how to stop it. I arrived back at the airport after a weeklong trip to the west coast - threw my backpack onto the passenger seat and started driving home. After around 10 mins I got a seatbelt warning chime and light - I checked I was actually buckled in (I was) and after 20 seconds or so the chime stopped.... I assumed that a sensor was about to fail and was quietly annoyed. 5 mins later it went off again. This time I noticed it was the passenger seat that was alarming. It had mistaken the weight of my backpack as a passenger and was getting annoyed that it wasn't buckled in. Is there anything I can do to turn this annoying warning off, or am I prohibited by my own car from putting anything of decent weight into the passenger seat?