A method for controlling a vehicle system includes controlling a vehicle system having powered units that propel the vehicle system. A trip plan directs at least one of the powered units to remain in a non-propulsion generating mode during the trip. The method further includes slowing and/or stopping the vehicle system in contravention to the first trip plan, activating the at least one of the powered units out of the non-propulsion generating mode into an active, propulsion-generating mode when the vehicle system accelerates after the at least one of slowing or stopping in contravention to the first trip plan, and switching the at least one of the powered units back to the non-propulsion generating mode after the vehicle system achieves a designated speed following accelerating after the at least one of the slowing or stopping of the vehicle system in contravention to the first trip plan.