Brake-by-wire system having conditioned full brake force application termination at key off

An electric powered brake system (10) for braking road-engaging wheels of a motor vehicle. An ignition switch for turning a motor of the vehicle on and off also controls the application of electric power to the electric powered brake system. A control and method for maintaining application of full electric power to the electric powered brake system when the ignition switch is operated from ON to OFF so long as at least one parameter related to a respective component of the vehicle and indicative of a need to maintain full electric power application to the brake system continues to exist and for discontinuing application of full electric power to the brake system when all of selected ones of several such parameters are indicative of lack of need to maintain full electric power application to the brake system.