VCDS TT MK1: Simplifying the Complex Brake Bleeding Process

Bleeding the brakes on a TT MK1 (Audi TT, 1999 > 2007) can seem daunting, especially when deciphering the manual. However, using VCDS (Vag-Com Diagnostic System) software can significantly streamline this process. This guide outlines a step-by-step procedure for bleeding brakes on a Vcds Tt Mk1, utilizing a Motive power bleeder and Ross-Tech VCDS software.

Guided Brake Bleeding with VCDS on a TT MK1

This process, initially confusing due to the manual’s ambiguity regarding pedal pumping and bleeder valve positions, was simplified by the VCDS software’s guided instructions. Here’s a breakdown:

Preparing for the Bleed

1. Close All Bleeder Valves: Ensure all bleeder valves on the calipers are completely closed before starting.
2. Connect the Power Bleeder: Attach the Motive power bleeder to the brake fluid reservoir and maintain a pressure below 1 BAR (approximately 10 psi).

Initiating the VCDS Guided Procedure

1. Connect VCDS and Select Chassis: Connect the VCDS interface to the OBD-II port, turn on the ignition, and select “Auto-Scan” from the main screen. Choose “Chassis 8N – Audi TT (1999 > 2007)”.
2. Access ABS Brakes Module: Return to the main screen and select “Select.” Then, choose “03-ABS Brakes.”
3. Initiate Basic Settings: Within the 03-ABS Brakes module, select “Basic Settings – 04.”
4. Follow On-Screen Prompts: The VCDS software will display “Group 000.” Click the “Up” button to reach “Group 001 Brake Pump Bleeding Instructions.” Follow the on-screen instructions precisely.

Bleeding Sequence and Instructions

The VCDS software will guide you through the following:

1. Press and Hold Pedal: Press the brake pedal and hold it. The pump will engage. Release the pedal when instructed.
2. Open Front Bleeder Screws: The software will prompt you to open the front left (FL) and front right (FR) bleeder screws. Allow fluid to flow until clear and free of bubbles.
3. Close Front Bleeder Screws: Close the front bleeder screws and click “Up” in VCDS to proceed to the next step.
4. Repeat for Remaining Bleeders: Continue following the VCDS prompts, which will guide you through further steps involving pressing the pedal and opening/closing bleeder screws. This process might involve multiple repetitions for the front brakes before moving to the rear.

Traditional Bleeding After VCDS Guidance

After the initial VCDS-guided steps, perform a traditional bleed using the power bleeder:

1. Bleed Each Caliper: Following the sequence LF, RF, LR, RR:
   • Open the bleeder screw.
   • Allow fluid to flow until bubble-free.
   • With the bleeder screw open, slowly pump the brake pedal five times.
   • Close the bleeder screw and replace the rubber cap.
   • Move to the next caliper.

Post-Bleed Procedure and Verification

Following the bleed, perform a brake bedding procedure with new pads and rotors:

• Seating Procedure: Conduct four cycles of accelerating to 45 mph and moderately braking to 15 mph. Then, perform ten cycles of accelerating to 60 mph and hard braking to 15 mph. Allow for cooling periods between cycles.

Finally, a VCDS scan confirmed a successful bleed with no remaining fault codes in the ABS system. However, unrelated faults were found in the AWD system (Address 22), which require separate diagnosis.

This comprehensive approach, combining VCDS guidance with traditional bleeding techniques, ensures a thorough and effective brake bleed on a VCDS TT MK1. While initially complex, the VCDS software significantly simplifies the process. Remember to consult your vehicle’s specific repair manual for detailed torque specifications and safety procedures.