1) 1) SERVICE BRAKE RELEASED (NEW) SERVICE BRAKE RELEASED (NEW) FRONT 24 P1 BL2 BR1 BL1 25 45 P2 T1 BR2 T2 REAR S3 G1 23 PS B3 46 G2 PS T/M 23 PARKING T2 Return line P 6 Return line A B D B A Main pump L S1 955SA4BS02 When the pedal of brake valve (24) is released, the operating force is eliminated by the force of the spring, and the spool is returned. When the spool removes up, the drain port is opened and the hydraulic oil in the piston of axles return to the tank (26). Therefore, the service brake is kept released. 4-4-1 21 S1 20 P 23 PS PS 38 PP T1 6 8