BMW has issued recalls for about one million vehicles in North America over two separate problems it said raised the risk of fire.One recall affects BMW 3 series models from 2006 to 2011, which it says contain wiring that could cause the luxury sedans to overheat.The other recall involves a faulty valve heater installed in some 2007-2011 models.BMW said dealers will replace the faulty equipment for free.The firm expects to notify owners in December. Each problem potentially affects about 700,000 vehicles, according to the notification on the National Highway Traffic Safety Administration site. But BMW said the final tally is likely to be less than 1.4 million, due to overlaps.Most of the cars were sold in the US. The firm did not say whether a recall could affect cars outside of North America.BMW said it has been monitoring the wiring problem, which affects the heating and air conditioning system, since about 2008. “Wiring that overheats could cause the electrical connectors to melt, and increase the risk of a fire, even when the vehicle is unattended,” the firm said.There were injuries alleged in three cases in 2015, and a fourth incident in September, according to the safety recall report. After meeting with US regulators in October, the firm decided to issue a voluntary recall.BMW said it has been monitoring the valve heater issue since 2009. It has not received reports of injuries.The valve heater recall includes vehicles such as the 530i, the X3 and the Z4 3.01si.