Four Wheel Anti-Lock Brake System Hydraulic Control Unit

NOTE: This procedure only needs to be carried out if a new 4-wheel Anti-Lock Brake (4WABS) Hydraulic Control Unit (HCU) has been installed.

Clean all dirt from and remove the brake master cylinder filler cap, and fill the brake master cylinder reservoir with the specified brake fluid.
On vehicles with rear drum brakes, connect a clear drain tube to the right rear bleeder screw and the other end in a container partially filled with recommended brake fluid.
On vehicles with rear disc brakes, connect a clear drain tube to the right rear bleeder screw and the other end in a container partially filled with recommended brake fluid.
On all vehicles, have an assistant pump the brake pedal and then hold firm pressure on the brake pedal.
Loosen the right rear bleeder screw until a stream of brake fluid comes out. While the assistant maintains pressure on the brake pedal, tighten the bleeder screw. Repeat until clear, bubble-free fluid comes out. Refill the brake master cylinder reservoir as necessary.
On vehicles with rear drum and disc brakes, tighten the bleeder screw to specification. See TORQUE SPECIFICATIONS .
All vehicles, repeat Steps 2- 6 for the left rear bleeder screw, the right front bleeder screw and the left front bleeder screw, in that order. See BRAKELINE BLEEDING SEQUENCE .