Problems with airbags have become common fare lately, but seat belts are generally more cut-and-dried, though not always.
The National Highway Traffic Safety Administration is looking into two complaints of the front passenger seat belt in 2013 Hyundai Sonatas coming loose from the seat belt anchor pre-tensioner during a crash.
The reports included two injuries, but NHTSA's Office of Defects Investigation (ODI) said it is only counting one of the injuries, since the other one didn't involve the passenger belt.
In the injury accident, a Buena Park, Calif., consumer reported that the car was going about 25 miles per hour when another vehicle ran a red light and smashed into the Sonata.
Airbags deployed and the seat belts tightened as intended but "the passenger seat belt failed at the point where the lap restraint attaches to the car running board," the consumer said.
"The passenger that was wearing the failed seat belt during the accident was 110 pounds while the driver was 270 pounds. The driver's seatbelt functioned as intended while the passenger's detached," the complaint continued.
NHTSA is conducting a preliminary evaluation of the complaints. That could lead to a formal investigation which could eventually result in a recall.