Wendi Kunkel points out the key in the ignition on her 2010 Chevy Cobalt in Rockwall, Texas, in April. GM recalled millions of cars over a flaw in ignition switches that could cause the vehicles to shut off unexpectedly. LM Otero/AP hide caption

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Executive vice president and general counsel at General Motors Co. Michael Millikin (from left), GM CEO Mary Barra, CEO and president of Delphi Automotive PLC Rodney O'Neal and chairman of the firm at Jenner & Block Anton Valukas testify before a Senate Commerce, Science and Transportation Committee hearing. Jim Lo Scalzo/EPA/Landov hide caption

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The Chevrolet Cobalt is one of several GM models that were recalled for faulty ignition switches. The carmaker is paying a $35 million penalty. David Zalubowski/AP hide caption

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A Chevrolet logo on the grill of a 2013 Traverse at the 2013 Pittsburgh Auto Show. General Motors is recalling more than 1.5 million vehicles, including SUVs, vans and Cadillacs, for defective ignition switches and other problems. Gene J. Puskar/AP hide caption

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Laura Christian, far right, talks about how her birth daughter Amber Marie Rose was killed on July 29, 2005, in a car crash that investigators determined was linked to a defective ignition switch. J. Scott Applewhite/AP hide caption

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As members of Congress prepared to hear testimony from GM's CEO Tuesday, Ken and Jayne Rimer, whose daughter, Natasha Weigel, died in the crash of a 2005 Chevy Cobalt, spoke at a news conference held by family members of deceased drivers. Jim Watson/AFP/Getty Images hide caption

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Ford says it sold the most F-series trucks since 2006. Here, a 2014 F-150 goes through quality control on the assembly line at Ford's Dearborn Truck Plant. Bill Pugliano/Getty Images hide caption

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Vehicles in the lot of a Northbrook, Ill., Toyota dealer last October. Scott Olson/Getty Images hide caption

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