Tesla is conducting its largest ever recall campaign, which affects approximately 90,000 Model S units, due to a seatbelt issue.

In an e-mail sent to customers, the automaker stated that the problem with the front seatbelt was discovered in a single example, which was not involved in a crash.

Bloomberg reports that the issue was spotted earlier this month and quotes a Tesla representative, who said:

In early November, a customer sitting in the front passenger seat turned to speak with occupants in the rear and the seat belt became disconnected. The seat belt is anchored to the outboard lap pretensioner through two anchor plates that are bolted together. The bolt that was supposed to tie the two anchors together wasn’t properly assembled.”

In the meantime, the manufacturer inspected more than 3,000 Model S vehicles and couldn’t find any issues. However, Tesla is playing it safe and will continue to examine all models, including the P85D, in a voluntary recall. The company’s dealers will inspect the cars after owners will schedule an appointment, either online, by phone or through e-mail.

Since the announcement, Tesla’s shares dropped 1.9 percent to $217.59, at 2:38 p.m., New York time, on November 20.

This isn’t the first time that the automaker conducted a recall and, two years ago, several examples were called in because of an improperly welded seat bracket.

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