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Brake Modulator/Brake Motor Pack Assembly (ABS)

The Antilock Brake System (ABS) brake modulator/brake motor pack assembly controls hydraulic pressure to the front calipers and rear calipers or rear wheel cylinders by modulating hydraulic pressure to reduce the tendency of wheel lock-up.

The basic ABS brake modulator configuration consists of gear subassemblies, ball screws, nuts, pistons, and hydraulic check valves. The ABS brake motor pack consists of three motors, three drive gears, and three Expansion Spring Brakes (ESBs). For more information, refer to BASE BRAKING MODE and ANTILOCK BRAKING MODE. Antilock Brake System (ABS)