During a Wednesday investor call, he said the automaker will discontinue the Model S sedan and Model X SUV, marking a decisive move away from legacy car programs and toward artificial intelligence and robotics. End of the road for Model S and Model X The chief executive made the decision clear during the call. “It’s time to basically bring the Model S and X programs to an end,” he said. “We expect to wind down S and X production next quarter.” The Model S and Model X are among the automaker’s oldest vehicles. Tesla Model X. Musk said the Fremont, California, factory that currently produces the two models will be repurposed.