BMW will recall around 150,000 vehicles in North America to fix a possible defect that may keep the front passenger airbag from opening in a crash, the world's biggest premium carmaker said on Thursday. The voluntary recall concerns the front passenger airbag seat sensor mat in certain 2004-2006 model year vehicles, a company spokesman in Munich said. Models affected include certain 2006 3-Series, 2004-06 5-Series and 2004-06 X3 vehicles. BMW said it would start sending letters to customers in late September and that affected owners could continue to drive their vehicles unless the airbag warning lamp and the passenger airbag “on-off” lamp illuminated simultaneously.