The auto industry's airbag troubles deepened on Saturday, as federal regulators said three big automakers will recall about 2.1 million older vehicles to fix defects that could cause airbags to deploy when they are not supposed to.
Toyota Motor, Fiat Chrysler Automobiles and Honda Motor have issued three earlier recalls to fix problems with a defective chip in the affected airbag systems. But the National Highway Traffic Safety Administration said on Saturday that "a small number of vehicles" fixed under those earlier actions had experienced inadvertent air bag deployments, hence the new recall.
An airbag going off suddenly could cause an accident, the agency said. There have been no known fatalities related to the problem, it said.
The latest air bag recalls were not related to a wider issue involving millions of vehicles recalled over Takata Corp air bags. U.S. safety regulators have said defective Takata air bag inflators in certain vehicles can rupture and spray metal fragments inside the vehicle.
NHTSA blamed the problems it reported on Saturday on "electrical noise" in the air bag system. The agency said a fully effective solution to the problem might not be available until late this year.
The NHTSA said the models affected were: 2002-2003 Jeep Liberty and 2002-2004 Jeep Grand Cherokees (about 750,000 vehicles); 2003-2004 Honda Odyssey; and 2003 Acura MDX (about 370,000 vehicles) and 2003-2004 Pontiac Vibe; Dodge Viper; and Toyota Corolla, Toyota Matrix, and Toyota Avalon (about 1 million vehicles, not all of which were sold in the United States.)
The agency said the affected models had a part called an electronic control unit that controls deployment of its air bags. An auto parts maker, TRW, supplied control units containing the same control circuit to all three automakers.
Although the recalls announced by the agency on Saturday are not related to the Takata cases, the NHTSA said there was an overlap, in that about 1 million of the vehicles affected were also covered in separate recalls of Takata air bag inflator systems.
The latest recall highlights the difficulty automakers and regulators have with increasingly complex electronic systems. The agency said in a statement it could take several months for the companies to get enough parts to fix all the vehicles involved.
In the Takata cases, Honda on Friday said it has confirmed that a Takata air bag inflator ruptured in a Jan. 18 crash in Texas that killed the driver. Prior to the incident that took place near Houston, air bags made by the Japanese company had been linked to at least five deaths.