System for Controlling Service Braking in Auxiliary Axle Wheel Brakes

A system for controlling a wheel brake on an auxiliary axle of a vehicle, comprising:

• an electro-pneumatic drive axle brake control valve configured to deliver fluid pressure from a fluid source to a first drive axle wheel brake on a drive axle of the vehicle responsive to a first electronic control signal;
• a first auxiliary axle brake control valve configured to deliver fluid pressure from the electro-pneumatic drive axle brake control valve to a first auxiliary axle wheel brake on the auxiliary axle of the vehicle responsive to a first fluid pressure control signal;
• and,
• a fluid control signal generating valve configured to generate the first fluid pressure control signal responsive to a command to apply a steer axle wheel brake on a steer axle of the vehicle.