Over 550,000 Toyota vehicles have been recalled due to a seat back defect that could increase the risk of injury. The National Highway Traffic Safety Administration (NHT) has issued a notice stating that second-row seat backs may fail to lock into position during a high-speed collision. Approximately 550,007 vehicles are potentially affected. The NHTSA advises owners to contact their dealership for free replacement of the return springs in the recliner assemblies.