In a pump apparatus of a washer system, a closure member closes an opening of a motor housing and an opening of a circuit box. The closure member includes a plurality of terminal receiving holes. Each corresponding terminal is inserted through a corresponding one of the terminal receiving holes. One end of each terminal is placed at an interior part of the pump apparatus and is electrically connected to a corresponding one of a motor received in the motor housing and a control circuit received in the circuit box while the other end of each terminal is placed at the exterior part of the pump apparatus and forms a connection contact that is electrically connectable with a corresponding connection contact of an external connector.