Four Wheel ABS Hydraulic Control Unit (HCU)

Note: This procedure only needs to be performed if the 4-wheel anti-lock brake (4WABS) hydraulic control unit (HCU) has been replaced or if the HCU lines have been opened.





1. Clean all dirt from and remove the brake master cylinder filler cap, and fill the brake master cylinder reservoir with the specified brake fluid.





2. Connect a clear waste line to the RH rear bleeder screw and the other end in a container partially filled with recommended brake fluid.
3. With the RH rear bleeder screw open, cycle the brake pedal until no more air is seen in the waste line.





4. Tighten the RH rear bleeder screw, and disconnect the waste line.





5. Repeat Steps 2, 3 and 4 for the LH rear bleeder screw, the RH front disc brake caliper bleeder screw, and the LH front disc brake caliper bleeder screw, in that order.





6. Connect the scan tool DCL cable adapter into the vehicle data link connector (DLC) under the dash, and follow the scan tool instructions.
7. Repeat the system bleed procedure as outlined in Steps 1 through 5.