Volkswagen Group of America is recalling 21,074 2012-2013 model-year Audi A6 and A7 luxury sedans so dealers can install a passenger occupant detection system repair kit, free of charge, the National Highway Traffic Safety Administration said.

In vehicles with heated and cooled seats, the passenger occupant detection system may malfunction and prevent the passenger-side air bags from deploying in a crash, NHTSA said. The recall affects Audi A6 cars manufactured from March 28, 2011, to March 25, 2013, and Audi A7 cars manufactured from Jan. 25, 2011, to March 19, 2013.

The recall is expected to begin in February. Vehicle owners can reach Audi customer service at (800) 253-2834. Volkswagen’s number for this recall is 74D1.