Elantra Touring, Airbag Light, Airbag warning light faulty? Options

[runester]

Hey all,
So, I am the proud owner of an 09 Touring SE, Pearl Black. I love this car! Traded my new Element (36K mile) because the mileage SUCKED.
Anyway, again, I really love this little car! And I have had more than my share of cars, both new and used. So, I notice the other day the passneger side airbag light's glowing with my son seated. He is only eleven, and weights close 100 lbs. Of course I perused the manual, (I am very anal about manuals anyway), and found that he may be a little light, as it were, nonetheless, I am certain he'd been heavy enough three weeks ago. History: Bought the car in early August to catch the tail end of summer and test the cars Title. Put 2K miles on it on a family trip up the California coast, I am from Los Angeles, with no problems whatsoever. It was, in fact, a joy to drive no matter where I was, be it winding my way through Big Sir's highway one at 40, or doing 80 on the 101, the Elantra was a dream! Now this airbag thing has me a bit uncomfortable in that all the safety features what my main attraction, second being MPG. I have read a couple of posts reflecting a simliar issue, and am curious about details.
Thanks in advance to any who can shed some light!
R.

[schmitty]

There is probably a sensor in the seat and when not enough weight is put on the seat, the airbag will not deploy. Maybe you just noticed now. Turn the car on and sit in the passenger seat, if the light goes off then your son is to small.