2005 Buick Century Brake Master Cylinder Bleeder Tool

You need to secure the mounting flange of the brake master cylinder in a bench vise so that the rear of the primary piston is accessible, remove the master cylinder reservoir cap and diaphragm, install suitable fittings to the master cylinder ports that match the type of flare seat required and also provide for hose attachment and transparent hoses to the fittings installed to the master cylinder ports, then route the hoses into the master cylinder reservoir, fill the master cylinder reservoir to at least the half-way point with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container, and ensure that the ends of the transparent hoses running into the master cylinder reservoir are fully submerged in the brake fluid. Then you can use a smooth, round-ended tool to depress and release the primary piston as far as it will travel, a depth of about 25 mm (1 in), several times, and observe the flow of fluid coming from the ports, continue to depress and release the primary piston until fluid flows freely from the ports with no evidence of air bubbles, remove the transparent hoses from the master cylinder reservoir, install the master cylinder reservoir cap and diaphragm, remove the fittings with the transparent hoses from the master cylinder ports, wrap the master cylinder with a clean shop cloth to prevent brake fluid spills and remove the master cylinder from the vise.

You need to remove all 4 tire and wheel assemblies, inspect the brake system for leaks and visual damage and the battery state of charge, install a scan tool, and turn ON the ignition, with the engine OFF. With the scan tool, you can establish communications with the electronic brake control module (EBCM), and then bleed the base brake system, and follow the scan tool directions until the desired brake pedal height is achieved. When the desired pedal height is achieved, you can press the brake pedal to inspect for firmness, remove the scan tool, install the tire and wheel assemblies, inspect the brake fluid level, and road test the vehicle while inspecting that the pedal remains high and firm.

You will be needing a J 29532 diaphragm type brake pressure bleeder, or equivalent, and a J 35589-A master cylinder bleeder adapter.

You need to inspect the brake system for external leaks and use a scan tool to perform the antilock brake system automated bleeding procedure to remove any air that may have been trapped in the BPMV.