The president of Takata Corp., embroiled in a widening scandal regarding defective air bags, has stepped down.

Stefan Stocker, named president only 18 months ago, will be replaced by Shigehisa Takada, grandson of the company’s founder, a spokesman for the Japanese firm said. Takada will retain his more-senior post as chief executive of the company.

Takata, one of the world’s largest manufacturers of auto safety restraint systems, is responsible for defective air bags that have triggered recalls of more than 20 million vehicles globally.

The air bags, which can deploy with too much force upon impact, have been linked to multiple deaths.

Vehicles affected include those made by Honda — Takata’s biggest customer — as well as Nissan, Subaru, Ford, Chrysler, BMW, Mitsubishi and Mazda.

The recalls were followed by multiple class-action lawsuits and a congressional inquiry.

The first recalls tied to Takata air bags involved vehicles originally sold or currently registered in geographic locations associated with high humidity, including Puerto Rico, Hawaii, the U.S. Virgin Islands, Guam, Saipan, American Samoa, Florida and adjacent counties in southern Georgia, as well as the coastal areas of Alabama, Louisiana, Mississippi and Texas. Subsequent recalls were expanded to other geographic areas.