Brake System, Anti-Lock

The rear anti-lock brake system (RABS) is used on F-150, F-250, F-350 vehicles. The system consists of an anti-lock electronic control module (2C018), RABS valve, rear axle speed sensor and speed sensor ring. F-Super Duty vehicles are equipped with a speed sensor and speed sensor ring which are used for vehicle speed information. F-Super Duty vehicles are not equipped with the RABS system. For system diagnosis and testing, refer to Section 06-09A.

The four-wheel anti-lock brake system consists of an electronic control unit (ECU), an anti-lock hydraulic control unit (2C215) and system and pump motor relays. It also contains three sets of wheel speed sensors and speed sensor rings and a G-switch. Data which is continually transmitted by the wheel speed sensors and G-switch is monitored by the ECU. Microprocessors within the module process the data which is then translated into commands that activate the HCU when anti-lock function is necessary for optimum four-wheel braking performance. For diagnosis and testing, refer to Section 06-09B.