The National Highway Traffic Safety Administration has launched three unrelated investigations of the 2008 Chevrolet Impala, the 2011-2012 Dodge Charger, and the 2006-2008 Hyundai Sonata. Together, the safety probes affect nearly 750,000 car owners in the US.
2008 Chevrolet Impala: Units affected: 320,000
This investigation stems from a collision in Texas in which the Impala's driver's side front airbag deployed but the passenger's side bag didn't, leaving the passenger with substantially greater injuries. It's believed that the problem may be rooted in the software running the Impala's occupant classification system, which activates the passenger's side airbag when it detects a human sitting there. (For reference, the passenger weighed about 170 pounds, which should've been enough to turn on the airbag.) Though NHTSA has received just one complaint about this issue, there's data to suggest that the problem could affect a much larger number of Impalas, spanning from model year 2004 to 2010.
2011-2012 Dodge Charger: Units affected: 123,000
NHTSA's Office of Defects Investigation has received a total of 14 complaints from owners who claim that the Charger's alternator failed while the vehicle was in motion, which caused the engine to stall. One owner also reported smoke coming from the alternator following a stall. Thankfully, no accidents or injuries have yet been linked to the problem.
2006-2008 Hyundai Sonata: Units affected: 394,000
NHTSA says that there may be a problem with an electrical circuit located inside the Sonata's seatbelt buckle. If that circuit shorts out, it may prevent activation of the seatbelt pretensioner and the associated airbags, which would greatly increase the risk of injury during a collision. NHTSA has received a total of 83 complaints about the problem, and in most cases, drivers were alerted to the issue via a warning light on the dashboard. No accidents or injuries have been linked to the issue.
These investigations are the first step in NHTSA's three-step recall process. The agency will examine complaints from owners, and if there's enough consistency among them, the probes will move to phase two, the Engineering Analysis, in which NHTSA staff, working with automakers, will attempt to recreate the problems under lab conditions. Depending on how those tests go, NHTSA may ask for a full recall of these models.