New York CNN  — 

The National Highway Traffic Safety Administration has opened an investigation into model year 2022 and 2023 Tesla Model X SUVs because there may be a problem with their front seatbelt attachments.

NHTSA will launch an investigation when there’s reason to believe there may be a safety issue requiring action such as a recall. An investigation may, or may not, eventually result in a recall.

Tesla is already facing NHTSA investigations into its Autopilot and “Full Self Driving” driver assistance system and for steering wheels that came loose.

While the investigation applies to about 50,000 Model X vehicles, the problem has been found on only two, according to NHTSA’s report of the investigation. In these two SUVs a front seatbelt pretensioner, a small device that automatically pulls the seatbelt tight in the event of a crash, became disconnected from the seat frame. The pretensioners were not properly secured during assembly, NHTSA said.

Both incidents happened while the vehicles were being driven at low speeds and the SUVs involved were still relatively new, and had not been driven very many miles.

NHTSA is investigating to determine if this is a more widespread issue and not just a couple of isolated cases. In one complaint on NHTSA’s website that fits the description of the problem, the seatbelt became detached when the SUV braked suddenly to avoid hitting something.

Tesla was recently required to officially recall 363,000 vehicles to update the “Full Self Driving” driver assistance software. In that case, the safety recall was done using an over-the-air software update. If NHTSA finds that the seatbelt situation requires a recall, that would probably require manual work by a Tesla technician.