IRVINE, CA -- Kia Motors is recalling more than 72,500 of its Rio vehicles due to a defective circuit board sensor mat.

According to Kia, the defective mats can experience fatigue cracking, and if sufficient cracking occurs, the sensor that determines whether a child is riding in the front seat would malfunction, leading the airbag to deploy during a crash. Most cars sold in the US today are equipped with such sensors to prevent the air bag from deploying if a small passenger is in the front due to increased risk of injury to the occupant.

The recall covers cars of the model years 2006 - 2008, manufactured between Feb. 20, 2005, and Dec. 9, 2007.

It is presently unclear whether the cause of the defect is faulty design or defective boards.