A vehicle control system receives a proximity signal at a sensor assembly from a vehicle system. The proximity signal indicates that the vehicle system is approaching a location of the sensor assembly. A sensor of the sensor assembly is activated responsive to receiving the proximity signal. One or more characteristics of the vehicle system are sensed as the vehicle system moves by the sensor assembly. A sensor signal that represents the one or more characteristics of the vehicle system is communicated to an onboard controller of the vehicle system and/or an off-board system to control operation of the vehicle system based on the one or more characteristics of the vehicle system.