Abstract: An infusion pump which may include a control unit and a pump engine may be used to facilitate administration of medicinal fluids to a patient. A control unit may include a motor, a controller, a housing, and a motor coupling, where the motor coupling includes two protruding motor coupling tabs extending in a direction parallel to an output shaft of the motor. A pump engine may include a housing, a rotor disposed in the housing, and a pump coupling, where the pump coupling includes at least two protruding pump coupling tabs extending in a direction parallel to an input shaft of the rotor. The controller may be configured to change an operational mode of the infusion pump, where when the infusion pump is in a positioning mode, the controller activates the motor to move the output shaft to a predetermined angular position.