Suzuki is recalling 193,936 cars and SUVs because of a defective air bag sensor in the front passenger seat. Grand Vitara SUVs from the 2006 through 2011 model years and SX4 small cars from the 2007 through 2011 model years are involved. Sensor mats measure passengers’ weight and determine if the air bag should deploy. Determining who sits in the seat is important because the force of an air bag can injure children or small adults.