The widening inquiry adds autos made by Fiat Chrysler Automobiles NV, Toyota Motor Corp., Honda Motor Co. and Mitsubishi Motors Corp. from model years 2010 through 2019. (Photo: Shutterstock) The widening inquiry adds autos made by Fiat Chrysler Automobiles NV, Toyota Motor Corp., Honda Motor Co. and Mitsubishi Motors Corp. from model years 2010 through 2019. (Photo: Shutterstock)

The U.S. National Highway Traffic Safety Administration (NHTSA) is investigating a possible deadly flaw in some 12.3 million vehicles that could prevent airbags from deploying in a crash.

The agency is examining airbag control units supplied by parts maker ZF-TRW that could fail due to “electrical overstress” and prevent airbags and seat belt pretensioners from activating as normal in a crash, NHTSA said in a notice on its website Tuesday.

Related: Faulty airbag parts prompt Honda to recall 1 million cars

NHTSA expands preliminary probe

The move is a significant expansion of the preliminary probe NHTSA began last year, which initially focused on certain Hyundai and Kia vehicles. The widening inquiry adds autos made by Fiat Chrysler Automobiles NV, Toyota Motor Corp., Honda Motor Co. and Mitsubishi Motors Corp. from model years 2010 through 2019.

NHTSA said it’s identified two substantial crashes — including one that resulted in a fatality — in which airbags didn’t deploy in Toyota cars and that electrical overstress is the suspected cause. In an emailed statement, Toyota said it’s cooperating with NHTSA’s analysis, investigating the issue and will take appropriate action.

Fiat Chrysler recalled 1.4 million vehicles with the affected airbag control units in 2016, and NHTSA said it hasn’t found related failures on other vehicles made by the company. An FCA spokesman said the company will cooperate with NHTSA’s investigation.

Related: Costly 2018 recalls prove the need for product liability insurance

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