A redundant brake control system for a locomotive consist that employs corresponding air brake control units in each locomotive that are interconnected by an inter-unit cable extending between the locomotives. Power to the air brake control units may be selectively connected and disconnected to select which air brake control unit is controlling the brakes of the train. The electronic brake valves associated with the air brake control units remain powered so that braking command may be send from either electronic brake valve and responded to by whichever of the air brake control valves have been provided with power. The control of power may be performed by the locomotive control system so that an operator can easily switch control between the air brake control units from the cab of any locomotive in the consist.