The “check engine” light lit up almost as soon as Mike Manley took over as chief executive of Fiat Chrysler Automobiles NV. Days before the late Sergio Marchionne died unexpectedly a year ago, Manley was tasked with leading the Italian-American company into an automotive era increasingly defined by progress in electrification and self-driving technology. Right after being named CEO, he was forced to cut financial targets due to disappointing sales in China. The company rattled investors again six months later by lowering 2019 earnings guidance.