4 1 3 43 2 41 42 41 42 43 22 11 21 WL Truck ABS WL Parking WL Service Brake IL Trailer from CAN J 1939 WL Trailer ABS Knorr-Bremse Antilock Braking System for Trucks - 4S/4M 1 2 3 24 25 26 8 9 6 5 7 17 18 19 20 11 12 10 13 14 15 22 23 21 27 4 16 P-00291/LT-ABS 13.10.2003 EN Service Brake Supply Parking Brake Air Suspension Auxiliary Equipment Electrical Signal T/AS2 0 2 1 1 2 1 2 21 22 23 24 3 3 3 1 2 3 11 21 12 22 3 1 1 11 12 11 12 11 22 21 2 2 3 3 4 2 3 1 2 3 1 1 Compressor 2 Air Processing Unit 3 Air Reservoir Circuit 1 4 Air Reservoir Circuit 2 5 Pressure Switch Circuit 1 6 Pressure Switch Circuit 2 7 Foot Brake Valve 8 ABS Modulator Valve 9 Bake Chamber 10 Sensing Ring and Speed Sensor 11 ABS-ECU 12 Load Sensing Valve 13 Spring Brake 14 Air Disc Brake 15 Brake Disc 16 Air Reservoir Circuit 3 17 Check Valve 18 Hand Brake Valve 19 Relay Valve 20 Pressue Switch 21 Trailer Control Valve 22 Coupling Head "Supply" 23 Coupling Head "Control" 24 ABS-Connection ISO 7638 25 Solenoid Valve 26 Operating Cylinder 27 Test Connector WL Warning Lamp IL Information Lamp to Air Suspension KNORR-BREMSE Systems for Commercial Vehicles