BERLIN—Volkswagen has issued a recall for more than 150,000 Audi vehicles in the United States on concerns that their passenger air bags might not activate, according to a filing to the National Highway Traffic Safety Administration (NHTSA). The recall is expected to affect 153,152 Audi A3 cars built between 2015 and 2020, including the Sedan, Etron and Cabriolet models, as well as certain S3 Sedans. The system which detects whether the passenger seat is occupied might malfunction and switch off the air bag even if a person is sitting there, the filing said. Volkswagen will write to owners of the affected vehicles by May 21 and will contact them again once a solution to the problem has been found. By Caroline Copley