DETROIT (AP) -- U.S. safety regulators are trying to figure out if General Motors should expand the number of midsize cars that are being fixed under a May recall.
The probe affects the 2012 and 2013 Chevrolet Malibu Eco, Buick LaCrosse and Buick Regal sedans.
In May, GM recalled nearly 43,000 cars because a defective generator control module could stall the engine or cause a fire. The cars have GM's eAssist gas-electric hybrid system.
Under the recall, GM was to replace the modules in about 22,000 cars and test the remaining 21,000. But the government now says there was a fire in a car that had been tested. It's looking into whether the modules should be replaced in all the cars.
GM says the recall is continuing and it's cooperating in the investigation.
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