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Antilock Brakes / Traction Control Systems: Description and Operation

VCM/FOUR WHEEL ANTILOCK BRAKE SYSTEM (VCM/4WAL)

VCM Four Wheel Anti-Lock Brake System.:






This anti-lock system differs from the stand alone 4WAL systems because the electronic controls are located in the same module used to control the engine. This system reduces the occurrence of wheel lock-up during severe braking conditions by regulating hydraulic pressure to all four wheels. The pressure is regulated by the Brake Pressure Modulator Valve (BPMV), using signals it receives from the Vehicle Control Module (VCM). The VCM receives its signal from the vehicle speed sensor (VSS), wheel speed sensors, brake switch, pressure differential switch and transfer case switch.