Elon Musk was chastened by federal regulators on Saturday night, and he agreed to step down as chairman of Tesla and to have his communications monitored, the New York Times reported. But Musk, the exuberant, relentless billionaire chief executive of Tesla, showed no immediate signs of changing his style. On Sunday at 1:08 a.m., just hours after settling the Securities and Exchange Commission’s fraud case stemming from his impulsive tweet on Aug. 7, Musk sent an email to all Tesla employees. He implored them to work hard, even though it was the weekend. For all of Mr. Musk’s late-night enthusiasm, however, Tesla faces many challenges in the months ahead. The company is still struggling to produce and deliver its Model 3 cars, which are the key to its financial future. It is short on cash and has looming bond payments. Short-sellers are still targeting the company, betting on the stock to fall. The SEC is continuing to look into the company’s past claims about its production goals, and the Justice Department was also looking into Musk’s tweet.
