U.S. safety regulators are investigating complaints that two Nissan recalls didn't fix a problem with front-seat air bag seat sensors.
The probe covers nearly 990,000 vehicles that were recalled in 2013 and last year because computer software may not detect an adult in the passenger seat. If that happens, the air bags won't inflate.
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The recall affects the Altima midsize car, Leaf electric car, Pathfinder SUV and Sentra compact models from the 2013 and 2014 model years, as well as the NV200 Taxi van and Infiniti JX35 SUV from 2013.
Also covered are the Infiniti QX60 and Q50 SUVs from 2014.
The National Highway Traffic Safety Administration says 124 people have complained about the problem happening after repairs were made. Nissan maintains the fixes took care of the problem.