In the last year, General Motors has issued two small airbag-related recalls affecting a total of around 7,000 vehicles. But the folks at the National Highway Traffic Safety Administration think that recall may need to be expanded a little bit… by around 400,0000.

NHTSA announced today that it is investigating whether the defect, which could result in a short that prevents the main driver’s airbag from deploying in a crash, is more widespread than initially believed.

The first recall was for 3,000 model year 2012 Cruze, Verano and Sonic vehicles. Shortly thereafter, that recall was expanded by 3,900 vehicles. That second recall also included some 2012 Camaros.

The U.S. auto safety agency has opened an investigation to determine whether GM went far enough in issuing two small recalls for air bag problems in October 2012 and January 2013, to address a shorting bar defect in the driver’s frontal air bag connectors in certain 2012 Chevrolet Cruze, Sonic and Camaro as well as Buick Verano vehicles.

“To identify the scope of each of the two recalls, GM stated it conducted an investigation of the root cause and an analysis of the warranty claim data, including a review of claim rates by air bag inflator build date,” reads today’s statement from NHTSA. “However, among other things, it appears that a production issue (root cause) was not fully identified, particularly for the second recall.”

A rep for GM tells the AP that the investigation process “is just beginning… We recalled vehicles that we believe have an issue.”

U.S. investigating 400,000 GM cars for air bag defects [Detroit News]

US safety agency may expand GM air bag recall [AP]

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