| Description and Operation The traction control system is an expanded version of the anti-lock brake system. The system is integrated with the anti-lock brake system and uses the same wheel speed sensors and hydraulic control unit (HCU). The HCU has additional internal solenoid valves incorporated to enable control modulation of the wheel brake pressures. Brake Traction Control System (BTCS) Brake traction control uses controlled braking of the spinning driving wheel, when the grip at the driven wheels are different. The BTCS system is only active at road speeds up to 50 km/h (30 mph). When the system is active the driver is made aware of the fact by the illumination of a warning indicator located in the instrument cluster. The spinning wheel is braked by the ABS system. This transfers a greater proportion of the engine torque through the differential to the other driven wheel, thereby increasing the utilization of the available traction. | 
