TM 9-2320-272-24-1
1-23. COMPRESSED AIR AND BRAKE SYSTEM OPERATION (Contd)
c. Secondary Service Airbrake System Operation.
(1) The secondary service airbrake system is made up of two subsystems:
(a) Secondary constant pressure system provides continuous air pressure to:
l Pedal valve
l Rear relay valve
Spring brake air reservoir
l
Spring parking brake valve
l
(b) Secondary signal system serves three functions:
Contains air pressure only when operator steps on brake pedal.
l
l Is regulated by various valves to control amount of braking.
Provides pressure to apply rear two service brakes and intermediate and rear axles
l
stamped with B. Service brakes on rear axle are piggybacked to spring brakes, but operate
independently of them.
(2) The secondary constant pressure system is made up of the following components:
1-60
