Members of Tesla’s board are scrambling to control a chief executive who some directors think is...: Members of Tesla’s board are scrambling to control a chief executive who some directors think is out of control. Elon Musk, the electric-car maker’s co-founder and chief executive, stirred up a public storm by announcing on Twitter last week that he wanted to turn Tesla into a private company. In recent days, according to people familiar with the matter, some of his fellow board members delivered a stern message: Stop tweeting. Mr. Musk hasn’t heeded that advice.