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Brake Fluid: Bleeding

CAUTION: Bleeding without the Techstream may result in air remaining in the brake hydraulic system. As this can cause an accident, be sure to use the Techstream for air bleeding.
NOTE:
  • Move the shift lever to the P position and apply the parking brake before bleeding the brakes.
  • Add brake fluid to keep the level between MIN and MAX lines of the reservoir while bleeding the brakes.
  • If the pump motor operates while air remains inside the No. 1 reservoir tube, the air will enter the actuator, resulting in difficulty in bleeding. Keep the 2 ABS motor relays removed until instructed to reinstall them to prevent air from entering the No. 1 reservoir tube.
  • The actuator pump motor and solenoid can be operated by the driver even if the power switch is OFF.
  • Although a buzzer may sound due to declined accumulator pressure during bleeding, continue bleeding.
  • DTCs indicating a malfunction in the ABS motor relay or pressure sensor are stored after bleeding. Clear the DTCs when instructed during or after bleeding.

Work list 

WORK LIST

Item Work procedure
Brake fluid (replacement) (1)(2)
  1. Disable brake control (remove 2 ABS motor relays before replacement).
  2. Bleed air from the front brake system.
  3. Bleed air from the rear brake system.
Brake master cylinder and stroke simulator (replacement) (1)(2)
  1. Perform accumulator zero down (before replacement).
  2. Disable brake control (remove 2 ABS motor relays before replacement).
  3. Bleed air from the No. 1 reservoir tube.
  4. Bleed air from the front brake system.
  5. Bleed air from the rear brake system.
  6. Perform accumulator zero down.
Brake actuator (replacement) (1)
  1. Perform accumulator zero down (before replacement).
  2. Disable brake control (remove 2 ABS motor relays before replacement).
  3. Bleed air from the No. 1 reservoir tube.
  4. Bleed air from the front brake system.
  5. Bleed air from the rear brake system.
  6. Perform accumulator zero down.
Front brake (removal, Installation, and disassembly) (1)
  1. Disable brake control (remove 2 ABS motor relays before removal, installation, and disassembly).
  2. Bleed air from the front brake system.
Rear brake (removal, installation, and disassembly) (1)
  1. Disable brake control (remove 2 ABS motor relays before removal, installation, and disassembly).
  2. Bleed air from the rear brake system.
(1) The listed order must be followed.
(2) If air enters the No. 1 reservoir tube due to declined brake fluid level, be sure to bleed the No. 1 reservoir tube.

HINT:

Refer to the Techstream operator's manual for further details.

  1. DISABLE BRAKE CONTROL 
    1. Move the shift lever to the P position and apply the parking brake.
    2. Connect the Techstream to the DLC3 with the power switch OFF.
    3. Remove the 2 ABS motor relays from the engine room No. 3 relay block.
    4. Turn the power switch ON (IG).
      NOTE: Do not start the engine.
    5. Turn the Techstream on and enter the following menus: Chassis / ABS/VSC/TRC / Utility / Electronically Controlled Brake system Utility / Electronically Controlled Brake system Invalid.
      Fig 1: Locating ABS Motor Relays
      G05816458Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. FILL RESERVOIR WITH BRAKE FLUID 
    NOTE:
    • If brake fluid leaks onto any painted surface, wash or otherwise remove it completely.
    • Do not place the fluid can on the reservoir inlet because brake fluid may overflow.
    1. Add brake fluid into the reservoir.

      Fluid: 

      SAE J1703 or FMVSS No. 116 DOT 3 

      Fig 2: Filling Brake Fluid Into Reservoir
      G05816459Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. BLEED AIR FROM NO. 1 RESERVOIR TUBE 
    1. Connect SST to the reservoir with the brake reservoir pressure adapter.

      SST 09992-00242, 09992-00350 

    2. Connect a vinyl tube to the bleeder plug of the actuator.
    3. Loosen the bleeder plug of the actuator.
    4. Use SST to boost the pressure in the reservoir.

      Standard pressure: 

      50 to 80 kPa (0.5 to 0.8 kgf/cm 2  , 7.3 to 11.6 psi) 

      Fig 3: Connecting SST To Reservoir With Brake Reservoir Pressure Adapter
      G05816460Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Drain approximately 100 cc (6.1 cu.in.) of brake fluid.
    6. Tighten the bleeder plug and boost the pressure in the reservoir again. Then loosen the bleeder plug to bleed air.
      NOTE: Repeat the above procedures 5 times.
    7. When air is completely bled from the hose between the reservoir and the actuator, tighten the bleeder plug.

      SST 09023-00101 

      Torque: 8.3 N*m (85 kgf*cm, 74 in.*lbf) 

  4. BLEED AIR FROM BRAKE MASTER CYLINDER 
    NOTE: If the master cylinder has been disassembled or if the reservoir becomes empty, bleed air from the master cylinder.
    1. Disconnect the brake lines from the master cylinder.
    2. Slowly depress and hold the brake pedal.
      Fig 4: Depressing Brake Pedal
      G05816461Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Cover the outer holes with fingers, and release the brake pedal.
    4. Repeat the above procedures 3 or 4 times.
    5. Using SST, connect the brake lines to the master cylinder.

      SST 09023-00101 

      Torque: 15 N*m (155 kgf*cm, 11 ft.*lbf) without 

      SST 

      14 N*m (144 kgf*cm, 10 ft.*lbf) with SST 

      Fig 5: Releasing Brake Pedal
      G05816462Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      • Use a torque wrench with a fulcrum length of 300 mm (11.81 in.).
      • This torque value is effective when SST is parallel to a torque wrench.
  5. BLEED AIR FROM FRONT BRAKE SYSTEM 
    NOTE: Bleed air from the wheel furthest from the master cylinder.
    1. Turn the power switch ON (IG) and turn the Techstream on.
    2. Cancel "DISABLE BRAKE CONTROL" on the Techstream.
    3. Connect a vinyl tube to the bleeder plug.
    4. Depress the brake pedal several times, then loosen the bleeder plug with the pedal depressed.
      Fig 6: Loosening Bleeder Plug With Pedal Depressed
      G05297211Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. When fluid stops coming out, tighten the bleeder plug, then release the brake pedal.
    6. Repeat the above procedures until all the air in the fluid is completely bled out.
    7. Tighten the bleeder plug to the specification.

      Torque: 11 N*m (112 kgf*cm, 8 ft.*lbf) 

    8. Repeat the above procedures for the other wheels to bleed the air from the brake line.
      Fig 7: Tightening Bleeder Plug
      G05297212Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. BLEED AIR FROM REAR BRAKE SYSTEM 
    NOTE: Bleed air by following the steps displayed on the Techstream.
    1. Turn the power switch OFF.
    2. Install the 2 ABS motor relays to the engine room No. 3 relay block.
      NOTE: Install 2 ABS motor relays before bleeding air from the rear brake system.
    3. Turn the power switch ON (IG) and turn the Techstream on.
    4. Cancel "DISABLE BRAKE CONTROL" on the Techstream.
    5. Clear the DTC.
    6. Turn the Techstream on and enter the following menus: Chassis / ABS/VSC/TRC / Utility / Electronically Controlled Brake system Utility / Electronically Controlled Brake system Invalid.
    7. With the brake pedal depressed, loosen the bleeder plug on the rear disc brake caliper LH.
      NOTE: Keep the fluid inside the reservoir above the MIN line by replenishing.

      HINT:

      • Depress and hold the brake pedal.
      • After the solenoid operates for approximately 30 seconds, release the brake pedal to stop the solenoid.
      • Repeat the above procedures until air is completely bled from the rear brake system.
      • The brake control warning light comes on and the buzzer sounds while bleeding, but they do not indicate a malfunction.
    8. Tighten the bleeder plug after bleeding.

      Torque: 11 N*m (112 kgf*cm, 8 ft.*lbf) 

    9. With the brake pedal depressed, loosen the bleeder plug on the rear disc brake cylinder RH.
      NOTE: Keep the fluid inside the reservoir above the MIN line by replenishing.

      HINT:

      • Depress and hold the brake pedal.
      • After the solenoid operates for approximately 30 seconds, release the brake pedal to stop the solenoid.
      • Repeat the above procedures until air is completely bled from the rear brake system.
      • The brake control warning light comes on and the buzzer sounds while bleeding, but they do not indicate a malfunction.
    10. Tighten the bleeder plug after bleeding.

      Torque: 11 N*m (112 kgf*cm, 8 ft.*lbf) 

    11. Cancel "DISABLE BRAKE CONTROL" on the Techstream.
  7. PERFORM ACCUMULATOR ZERO DOWN 
    CAUTION: Be sure to perform this procedure before removal of the actuator.
    NOTE: Perform accumulator zero down by following the steps displayed on the Techstream.
    1. Drain the brake fluid in the reservoir tank near the MIN line.
    2. Connect the Techstream to the DLC3 with the power switch OFF.
    3. Turn the Techstream on.
      NOTE: Repeat the following procedures 5 times.
      1. Turn the power switch ON (IG).
      2. Turn the Techstream on and enter the following menus: Chassis / ABS/VSC/TRC / Utility / Electronically Controlled Brake system Utility / Zero Down.
      3. When the buzzer sounds, turn the power switch OFF.
        NOTE: Keep the fluid inside the reservoir above the MIN line by replenishing.

        HINT:

        • Accumulator pressure is released and accumulated repeatedly, which circulates the fluid inside the accumulator zero down (accumulator depressurizing).
        • The pump motor rotates and accumulator is pressurized every time the power switch is turned from OFF to ON (IG).
  8. CHECK BRAKE FLUID LEVEL IN RESERVOIR 
    1. Adjust the brake fluid to the MAX line with the power switch on (IG).
  9. CLEAR DTC 
    1. Clear the DTCs (see DTC CHECK/CLEAR ).
  10. PERFORM LINEAR VALVE OFFSET LEARNING 
    1. When the brake actuator assembly is replaced, perform linear valve offset learning (see INITIALIZATION ).
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