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For 1990-2009 cars only

Hydraulic Brake System Bleeding Manual

    Warning: Refer to Safety Glasses Warning in the Preface section.

    Warning: Refer to Brake Dust Warning in the Preface section.

    Warning: Refer to Brake Fluid Warning in the Preface section.

    Warning: Refer to Brake Fluid Irritant Warning in the Preface section.

    Caution: Refer to Brake Fluid Effects on Paint and Electrical Components Caution in the Preface section.

    Danger: To avoid any vehicle damage, serious personal injury or death when major components are removed from the vehicle and the vehicle is supported by a hoist, support the vehicle with jack stands at the opposite end from which the components are being removed and strap the vehicle to the hoist.

  1. Place a clean suitable container beneath the brake master cylinder to catch brake fluid spills.
  2. Note: When adding fluid to the brake master cylinder reservoir, use only Super DOT 4 or DOT 4 Plus brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

    Note: With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort increases significantly, in order to deplete the brake booster power reserve.

  3. Deplete the brake booster power reserve.
  4. If you have performed a brake master cylinder bench bleed, disconnected the brake pipes from the master cylinder or the hydraulic modulator assembly, you MUST perform the following steps to bleed air at the ports of the hydraulic component:
  5. 3.1. Clean the outside of the reservoir on and around the reservoir cap prior to removal.
    3.2. With the brake pipes installed securely to the master cylinder or hydraulic modulator assembly, loosen and separate one of the brake pipes from the port of the component:

    For the hydraulic modulator assembly, perform these steps in the sequence of system flow; begin with the fluid feed pipes from the master cylinder.

    3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the component.
    3.4. Reconnect the brake pipe to the component and tighten securely.
    3.5. With the aid of an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
    3.6. Loosen the same brake pipe to purge air from the open port of the component.
    3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
    3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of each component.
    3.9. With the brake pipe installed securely to the master cylinder or hydraulic modulator assembly, and after all air has been purged from the first port of the component that was bled, loosen and separate the next brake pipe from the component, then repeat steps 3.3-3.8 until each of the ports on the component has been bled.
    3.10. After completing the final component port bleeding procedure, make sure that each of the brake pipe to component fittings is correctly tightened.
  6. Clean the outside of the brake master cylinder reservoir on and around the reservoir cap.
  7. Note:  Make sure the brake master cylinder reservoir remains at least half-full during this bleeding procedure. Add fluid as needed to maintain the correct level.

  8. Remove the master cylinder reservoir cap.
  9. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  10. Remove the wheels. Refer to Tire and Wheel Removal and Installation.

  11. Object Number: 1946451  Size: SH
  12. Fit a correct sized ring spanner onto the LEFT REAR wheel hydraulic circuit bleeder valve (1).
  13. Install a transparent hose over the end of the wheel hydraulic circuit bleeder valve (1).
  14. Submerge the open end of the transparent hose into a container partially filled with brake fluid from a clean, sealed brake fluid container.
  15. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
  16. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
  17. Tighten the bleeder valve, then have the assistant slowly release the brake pedal.
  18. Wait 15 seconds, then repeat steps 11-13 until all air is purged from the wheel hydraulic circuit.
  19. Tighten the wheel circuit bleeder valve securely.
  20. Fit a correct sized ring spanner onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
  21. Repeat steps 9-15.
  22. Fit a correct sized ring spanner onto the LEFT FRONT wheel hydraulic circuit (inboard GXP) bleeder valve.
  23. Repeat steps 9-15.
  24. For GXP models, fit a correct sized ring spanner onto the LEFT FRONT wheel hydraulic circuit outer bleeder valve.
  25. Repeat steps 9-15.
  26. Fit a correct sized ring spanner onto the RIGHT FRONT wheel hydraulic circuit (inboard GXP) bleeder valve.
  27. Repeat steps 9-15.
  28. For GXP models, fit a correct sized ring spanner onto the RIGHT FRONT wheel hydraulic circuit outer bleeder valve.
  29. Repeat steps 9-15.
  30. After completing the final wheel hydraulic circuit bleeding procedure, make sure that each of the 4 wheel hydraulic circuit bleeder valves is correctly tightened.
  31. Install the wheels. Refer to Tire and Wheel Removal and Installation.
  32. Lower the vehicle.
  33. Fill the brake master cylinder reservoir to the maximum-fill level with brake fluid from a clean, sealed brake fluid container.
  34. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  35. Note: If it is determined that air was induced into the system upstream of the hydraulic modulator assembly prior to servicing, the Antilock Brake System Automated Bleed Procedure must be performed. Refer to Antilock Brake System Automated Bleed Procedure.

  36. If the brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy after repeating the bleeding procedure, perform the following steps:
  37. 31.1. Inspect the brake system for external leaks. Refer to Brake System External Leak Inspection.
    31.2. Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped in the system.
  38. Turn the ignition ON, engine OFF. Check to see if the brake system warning lamp is illuminated.
  39. Note: DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

  40. If the brake system warning lamp is illuminated, refer to Symptoms - Hydraulic Brakes.

Hydraulic Brake System Bleeding Pressure

Special Tools

    • J 29532 Diaphragm Pressure Bleeder
    • J 35589-A Brake Pressure Bleeder Adapter

    Warning: Refer to Safety Glasses Warning in the Preface section.

    Warning: Refer to Brake Dust Warning in the Preface section.

    Warning: Refer to Brake Fluid Warning in the Preface section.

    Warning: Refer to Brake Fluid Irritant Warning in the Preface section.

    Caution: Refer to Brake Fluid Effects on Paint and Electrical Components Caution in the Preface section.

    Danger: To avoid any vehicle damage, serious personal injury or death when major components are removed from the vehicle and the vehicle is supported by a hoist, support the vehicle with jack stands at the opposite end from which the components are being removed and strap the vehicle to the hoist.

  1. Place a clean suitable container beneath the brake master cylinder to catch brake fluid spills.
  2. Note: When adding fluid to the brake master cylinder reservoir, use only Super DOT 4 or DOT 4 Plus brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

    Note: With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal becomes firm, in order to deplete the vacuum brake booster power reserve.

  3. Deplete the vacuum brake booster power reserve.
  4. If you have performed a brake master cylinder bench bleed, disconnected the brake pipes from the master cylinder or the brake pressure modulator valve (BPMV), you MUST perform the following steps to bleed air at the ports of the hydraulic component:
  5. 3.1. Clean the outside of the reservoir on and around the reservoir cap prior to removal.
    3.2. With the brake pipes installed securely to the master cylinder or BPMV, loosen and separate one of the brake pipes from the port of the component:

    For the BPMV, perform these steps in the sequence of system flow; begin with the fluid feed pipes from the master cylinder.

    3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the component.
    3.4. Reconnect the brake pipe to the component and tighten securely.
    3.5. With the aid of an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
    3.6. Loosen the same brake pipe to purge air from the open port of the component.
    3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
    3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of each component.
    3.9. With the brake pipe installed securely to the master cylinder or BPMV, and after all air has been purged from the first port of the component that was bled, loosen and separate the next brake pipe from the component, then repeat steps 3.3-3.8 until each of the ports on the component has been bled.
    3.10. After completing the final component port bleeding procedure, make sure that each of the brake pipe to component fittings is correctly tightened.
  6. Clean the outside of the reservoir on and around the reservoir cap.
  7. Remove the master cylinder reservoir cap and diaphragm.
  8. Fill the brake master cylinder reservoir to the maximum-fill level with brake fluid from a clean, sealed brake fluid container.
  9. Set up the brake pressure bleeder following the manufacturer instructions.
  10. Open the brake pressure bleeder fluid valve to allow pressurized brake fluid to enter the brake system.
  11. Note: Any brake fluid leaks identified require repair prior to completing this procedure.

  12. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to make sure that there are no existing external brake fluid leaks.
  13. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  14. Remove the wheels. Refer to Tire and Wheel Removal and Installation.

  15. Object Number: 1946451  Size: SH

    Note:  Make sure the brake master cylinder reservoir remains at least half-full during this bleeding procedure. Add fluid as needed to maintain the correct level.

  16. Fit a suitable tool onto the LEFT REAR wheel hydraulic circuit bleeder valve (1).
  17. Install a transparent hose over the end of the wheel hydraulic circuit bleeder valve (1).
  18. Submerge the open end of the transparent hose into a container partially filled with brake fluid from a clean, sealed brake fluid container.
  19. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow until air bubbles stop flowing from the bleeder, then tighten the bleeder valve.
  20. Tighten the wheel circuit bleeder valve securely.
  21. Fit a suitable tool onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
  22. Repeat steps 13-15.
  23. Tighten the wheel circuit bleeder valve securely.
  24. Fit a suitable tool onto the LEFT FRONT wheel hydraulic circuit (inboard GXP) bleeder valve.
  25. Repeat steps 13-15.
  26. Tighten the wheel circuit bleeder valve securely.
  27. For GXP models, fit a correct sized ring spanner onto the LEFT FRONT wheel hydraulic circuit outer bleeder valve.
  28. Repeat steps 13-15.
  29. Tighten the wheel circuit bleeder valve securely.
  30. Fit a suitable tool onto the RIGHT FRONT wheel hydraulic circuit (inboard GXP) bleeder valve.
  31. Repeat steps 13-15.
  32. Tighten the wheel circuit bleeder valve securely.
  33. For GXP models, fit a correct sized ring spanner onto the RIGHT FRONT wheel hydraulic circuit outer bleeder valve.
  34. Repeat steps 13-15.
  35. Tighten the wheel circuit bleeder valve securely.
  36. After completing the final wheel hydraulic circuit bleeding procedure, make sure that each wheel hydraulic circuit bleeder valve is correctly tightened.
  37. Close the brake pressure bleeder fluid valve.
  38. Install the wheels. Refer to Tire and Wheel Removal and Installation.
  39. Lower the vehicle.
  40. Remove the brake pressure bleeder from the brake master cylinder reservoir.
  41. Fill the brake master cylinder reservoir to the maximum-fill level with brake fluid from a clean, sealed brake fluid container.
  42. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  43. Note: If it is determined that air was induced into the system upstream of the BPMV prior to servicing, the Antilock Brake System Automated Bleed Procedure must be performed. Refer to Antilock Brake System Automated Bleed Procedure.

  44. If the brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy after repeating the bleeding procedure, inspect the brake system for external leaks. Refer to Brake System External Leak Inspection.
  45. Turn the ignition ON, engine OFF. Check to see if the brake system warning lamp is illuminated.
  46. Note: DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

  47. If the brake system warning lamp is illuminated, refer to Symptoms - Hydraulic Brakes.