The National Highway Traffic Safety Administration (NHTSA) has opened an investigation into possible seatbelt failures in 2022 and 2023 Tesla Model X electric SUVs, an issue that could affect up to 50,000 vehicles.

An investigation commenced after the NHTSA's Office of Defects Investigation (ODI) received two complaints reporting a failure of front seatbelts to remain connected to seatbelt anchors when worn properly, the agency said in a statement, noting that both vehicles that were the subject of the complaints "were delivered to owners with insufficiently connected anchor linkages."

Both reported incidents occurred at low mileage, and did not result in any injuries, the agency said.

2023 Tesla Model X - Courtesy of Tesla, Inc.

2023 Tesla Model X - Courtesy of Tesla, Inc.

Tesla seats have outboard pretensioners, the devices that cinch the seatbelts tight during abrupt deceleration to hold occupants in place, secured to the seat frame. The anchors for these pretensioners are designed to be disconnected with a special tool, and the two complaints indicate that failure occurred at the disconnection point, according to the NHTSA.

The safety agency believes that in certain vehicles the pretensioner and its linkage weren't properly connected during assembly. They were held in place merely by friction, and separated when force was applied to the connection point.

While it estimates that up to 50,000 vehicles could be impacted by the alleged assembly error, an investigation is not the same as a recall. The NHTSA said it will "assess the scope, frequency, and manufacturing processes associated with this condition," and direct Tesla to conduct a recall if necessary. The agency is also investigating reports of Tesla Model Y steering wheel detachment, but that hasn't gotten to the recall stage either.

2023 Tesla Model X - Courtesy of Tesla, Inc.

2023 Tesla Model X - Courtesy of Tesla, Inc.

Some of Tesla's recalls—including one of more than a million vehicles for pinch-prone power windows—have been easy via over-the-air fixes; seatbelt hardware, if defective, could require a hands-on fix.

Prices were cut on the Model X just earlier this month, lowering the base model by up to $10,000, but still leaving a base price of $101,380 for the least-expensive Dual Motor five-passenger version. The Model X was extensively refreshed for the 2021 model year, with a steering yoke, a larger, horizontally oriented interface, and redesigned interior—although the Falcon Wing door arrangement continued.