The feds are launching a trio of safety investigations on autos, first the Chevy Impala.
Investigators are looking at a new study from a California Company suggesting the weight sensor can malfunction and disable the front passenger air bag. This is for Impalas between 2007 and 2009. No defects have been found so far.
They're looking at similar problems in 2006 to 2008 Hyundai Sonatas. There have been dozens of complaints about an electrical problem knocking out air bags, or disabling the device that tightens seat belts before a crash.
The last is for 2011 and 2012 Dodge Chargers, where alternators have stalled while the cars were going at least 40 miles an hour. No one has been hurt.