Abstract: A method provides sleep and wake-up modes for railway track circuit units. An intermediate track circuit unit communicates in a first direction to a first unit and in a different second direction to a different second unit. A plurality of wireless messages are employed between a train and a plurality of wayside units operatively associated with some of the track circuit units. Included with the wireless messages are a first identifier of a corresponding one of the track circuit units and a second identifier of a direction of travel of the train. One of the wireless messages is received at one of the wayside units corresponding to the intermediate unit based upon the first identifier. A signal is responsively output based upon the second identifier from the intermediate unit in the first direction to the first unit or in the different second direction to the different second unit.