Hydraulic Control Unit (HCU)
This procedure is required only when a new hydraulic control unit is installed. A diagnostic tool, such as the Worldwide Diagnostic System, or equivalent, in necessary.
When any part of the hydraulic system has been disconnected for repair or new installation, air may get into the system and cause spongy brake pedal action. This requires bleeding of the hydraulic system after it has been correctly connected. See Bleeding the Brake System, under Brake Operating Systems.
Connect the diagnostic tool and follow the ABS system bleed instructions.
Use the manual bleed procedure(s) to bleed the system. Begin at the right rear caliper.