Abstract: Surge brake systems are used so that the brakes of towed vehicles can be applied automatically during slowing and stopping of towing vehicles. However, the known surge brake systems automatically apply the brakes to the towed vehicle during backing of the towing vehicle. The subject brake system includes a solenoid actuated valve which is disposed in a brake line to communicate a surge brake coupler to the brakes in a towed vehicle. A relay receives an electrical signal from an outputting device which places the valve in a closed position which disables the surge brake coupler and prevents the application of the brakes on the towed vehicle during backing of a towing vehicle. The relay receives an electrical signal from a producing device which overrides the electrical signal from the outputting means placing the valve in an open position. The open position of the valve allows application of the brakes on the towed vehicle so that braking is possible during backing of the towing vehicle.