Abstract: A pressurized air system controls air pressure in air reservoirs that deliver compressed air to air-actuated components in a vehicle. An air compressor supplies compressed air to air reservoirs which deliver compressed air to air-actuated components. A control system measures the air pressure in the air reservoirs by using at least one electric switch. Each switch is connected to an air reservoir and generates an electric signal to an electrically controlled valve indicative of the measured air pressure in the corresponding air reservoir. The electrically controlled valve is connected to an air compressor. The electrically controlled valve moves between a first position causing the air compressor to compress air and to supply compressed air to the air reservoirs and a second position causing the air compressor to stop compressing air, responsive to the received electronic signal.