The Sequence of Bleeding ABS Brakes

The Anti-lock Braking System (ABS), a pivotal innovation in the automotive industry in recent decades, enhances driving safety. However, its maintenance and upkeep require specific knowledge. Bleeding the ABS brake system is crucial as air within the system affects brake efficiency and ABS functionality. Here’s how to perform this procedure in the correct sequence.


  1. Importance of Bleeding the ABS Brake System: Air in the brake system is problematic because, unlike brake fluid, air is compressible. This leads to ineffective pedal depression, uneven braking, and a ‘soft’ feeling in the brake pedal if air is present in the system.
  2. Sequence of Bleeding the ABS Brake System: a) Preparation:
    • Check the brake fluid level and ensure the reservoir is full.
    • Use quality brake fluid that meets the specifications of the car manufacturer.
    • Safely lift the car using a jack. b) Bleeding Conventional Brake Calipers:
    • Before addressing the ABS module, bleed the conventional brake system.
    • Start with the wheel farthest from the brake fluid reservoir (usually the rear left wheel), followed by the rear right, front left, and finally the front right.
    • With an assistant’s help, press the brake pedal while opening the bleeder screw to release air and fluid. c) Bleeding the ABS Module:
    • As the ABS module requires special tools and techniques, many opt for professional services. However, if you have the right tools, follow these steps:
    • Connect the ABS bleeding tool to the OBD (On-Board Diagnostics) port.
    • Follow the tool’s instructions to activate the ABS module.
    • The tool activates valves to release air from the ABS module while continuously replenishing brake fluid to maintain the level.
    • Complete the bleeding process as indicated by the tool.
  3. Post-Procedure Checks:
    • Verify the brake fluid level and refill if necessary.
    • Test the brake system before lowering the car to ensure a firm pedal and no unusual sounds or vibrations.
    • Lower the car and conduct a test drive in a safe area.

While bleeding the ABS brake system may seem complex, it’s achievable with the proper tools and knowledge. However, if uncertain, always consult a professional. The car’s brake system is vital, and no risks should be taken with its safety.