NHTSA complaint: 2012 SUBARU IMPREZA — ELECTRICAL SYSTEM
The AC unit suddenly shutoff and there was a burning smell while I was driving. It turns out that the connector on the back of the climate control unit had either drawn too much current, or the resistance was too high, and the connector had started burning. Fortunately, the melted plastic interrupted the electrical connection, and the fire had went out on its own. It looks like this is not an isolated incident, and several others have dealt with similar when looking online.
National Highway Traffic Safety Administration — Office of Defects Investigation