Apparatus and Method for Isolating an Intact Portion of a Service Braking Circuit from a Failed Service Brake Wheel End

An apparatus for protecting an intact portion of a service brake system of a vehicle having at least two wheel ends from a failed wheel end, comprising:

• a spring brake actuator provided for each of the wheel ends for actuating a service brake and releasing a parking brake;
• a spring brake control valve for controlling actuation of the spring brake actuator for parking braking;
• a differential protection valve provided for each of the wheel ends for controlling a first supply of fluid to the spring brake actuator for releasing the parking brake;
• a relay valve for applying and releasing the service brake via the spring brake actuator;
• and
• a service brake isolation valve provided for each of the wheel ends for determining an operation state of each of the wheel ends and protecting the intact portion of the wheel ends individually, based upon the operation state.

A method of protecting an intact portion of a service brake system from a failed wheel end of a service brake system of a vehicle, comprising the acts of:

• determining that one of a plurality of wheel ends of the service brake system has failed;
• protecting the parking brakes at each of the plurality of wheel ends other than the failed wheel end such that the parking brakes do not actuate automatically;
• and
• maintaining service brakes at each of the plurality of wheel ends other than the failed wheel end.