Tesla is warning owners of its Model X SUV to not have anyone sit in the back of the vehicle until it can replace the third-row seat backs, which could fail in an accident. The automaker on Monday announced the voluntary recall of 2,700 Model X vehicles built before March 26 at the company's plant in Fremont, California. Tesla said it knows of no incidents where the hinge for a third-row seat has failed, but after a crash test, it determined the seat backs could collapse forward in some accidents.