The CEO of the manufacturer of the ignition switches that ended up in recalled General Motors cars said his company bears no responsibility for deaths resulting from the part, which was redesigned according to GM specifications.

"We had a product that we worked with General Motors to develop," Delphi Automotive's Rodney O'Neal told a Senate subcommittee looking into the ignition switch failure that caused at least 13 deaths among drivers and passengers in GM cars.

GM had asked that the torque in the switch be reduced, and Delphi redesigned the switch to comply, O'Neal said. GM has said all along that the torque on the switch could cause it to unintentionally move to the "accessory" or "off" position, turning off the engine and most of the electrical components in the car, including the air bags.

"Our product met the requirements of the customer," O'Neal said, referring to GM.

Asked by Nevada Republican Sen. Dean Heller if O'Neal thought his company bore any responsibility for the deaths, the CEO replied: "No. None."

GM CEO Mary Barra acknowledged that, "It's our responsibility."

Barra, who has been in front of lawmakers previously on the ignition switch problem, said GM was working hard to change the culture that led it to delay recalls for more than a decade.

"Overall, we are dramatically enhancing our approach to safety," she said.

Testimony by GM's General Counsel Michael Millikin that he didn't know about the ignition switch problem until February, just before the recalls began, prompted an angry response from Democratic Sen. Claire McCaskill of Missouri.

McCaskill said it was "either gross negligence or gross incompetency" for GM's lead attorney not to have known of the problem earlier.

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