Heat medium temperature adjustment system

A heat medium temperature adjustment system includes a heat medium circuit configured to circulate heat medium having a temperature controlled by a heat exchange with a heat source. The heat medium circuit includes a pump configured to pump the heat medium, and a plurality of heat exchangers for temperature-adjustment subjects configured to perform heat exchanges with temperature-adjustment subjects. The heat medium circuit is configured to form a series flow path to connect the pump to the plurality of heat exchangers for temperature-adjustment subjects when a system malfunction occurs.