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On-Vehicle Inspection [11/2021 - ]: Procedure

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  1. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK 
    1. When the ignition switch is turned to ON, check that the ABS warning light, brake system warning light (red indicator), brake system warning light (yellow indicator), VSC OFF indicator light, slip indicator light, brake hold standby indicator light and brake hold operated indicator light come on for approximately 3 seconds.

      HINT: 

      • When the brake fluid level is low, the brake system warning light (red indicator) comes on.
      • If the skid control ECU stores any DTCs, the ABS warning light, brake system warning light (red indicator), brake system warning light (yellow indicator) and slip indicator light will come on. Also, in this state, if the vehicle is under the following conditions and the brake hold switch (electric parking brake switch assembly) is turned on, the brake hold operated indicator light blinks.
        1. Vehicle Conditions:
          1. The driver door is closed.
          2. The driver seat belt is fastened.
      • If the warning lights and indicator lights does not illuminate or illuminates for more than approximately 3 seconds, perform troubleshooting for the electronically controlled brake system.

        Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

  2. INSPECT BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY 
    1. Disconnect the A46 brake booster with accumulator pump assembly connector.
      GTY1059813Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Brake Booster with Accumulator Pump Assembly)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A46-1 (BM1) - A46-2 (GND1) Always 10 Ω or less
  3. INSPECT BRAKE FLUID LEVEL WARNING SWITCH 
    1. Remove the brake master cylinder reservoir filler cap assembly.
      GTY1058585Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Brake Fluid Level Warning Switch (Brake Booster with Master Cylinder Assembly))
    2. Disconnect the A1 brake fluid level warning switch (brake booster with master cylinder assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      HINT: 

      A float is located inside the brake master cylinder reservoir assembly. Its position changes according to the level of brake fluid.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A1-1 (+) - A1-2 (E) Brake fluid level warning switch (brake booster with master cylinder assembly) off (float up) 1.84 to 2.16 kΩ
      A1-1 (+) - A1-2 (E) Brake fluid level warning switch (brake booster with master cylinder assembly) on (float down) Below 1 Ω
      (Brake fluid level is low)
    4. If there are no problems after completing the preceding inspection, adjust the brake fluid to the MAX level with the ignition switch turned to ON.
  4. BRAKE SYSTEM ON-VEHICLE INSPECTION 

    If no DTCs are output but the problem still occurs, use the following procedure to inspect the pressure sensor, brake booster with master cylinder assembly and stroke simulator.

    NOTE:

    DTCs may be stored during the inspection procedure. Be sure to clear the DTCs and check that no DTCs are output after the inspection is finished.

    1. INSPECT PRESSURE SENSOR
      1. Check the auxiliary battery voltage.

        Standard Voltage

        11 to 14 V (while the ignition switch is off)

      2. Set a pedal effort gauge and SST.
        GTY976676Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *a Pedal Effort Gauge *b SST (LSPV Gauge)
        *c SST (No. 1 Nipple) - -

        HINT: 

        Simultaneously measure the brake fluid pressure of all 4 wheels, or 2 wheels at a time.

        (1) Set a pedal effort gauge and SST.

        • SST: 09709-29018 
          1. 09709-00060

        (2) Park (P) selected and parking brake applied.

        (3) Bleed air from SST (LSPV gauge).

        Refer to BLEEDING [11/2021 - ]

      3. Inspect the master cylinder sensor 1, reaction force pressure and servo pressure.

        (1) Check the value output from "Master Cylinder Sensor 1", "Reaction Force Pressure" and "Servo Pressure" by depressing the brake pedal.

        Chassis > Brake/EPB > Data List 

        Tester Display
        Master Cylinder Sensor 1

        Chassis > Brake Booster > Data List 

        Tester Display
        Reaction Force Pressure
        Servo Pressure

        Standard Result

        Pedal Effort Reaction Force Pressure Servo Pressure Master Cylinder Sensor 1 Front Left Wheel Hydraulic Pressure Front Right Wheel Hydraulic Pressure
        50 N (5 kgf, 11.2 lbf) 0.00 to 0.64 MPa 1.02 to 5.02 MPa 0.72 to 4.72 MPa 0.72 to 4.72 MPa (7.34 to 48.13 kgf/cm2 , 104 to 684 psi) 0.72 to 4.72 MPa (7.34 to 48.13 kgf/cm2 , 104 to 684 psi)
        100 N (10 kgf, 22.5 lbf) 0.52 to 1.32 MPa 4.75 to 8.75 MPa 4.45 to 8.45 MPa 4.45 to 8.45 MPa (45.38 to 86.17 kgf/cm2 , 645 to 1225 psi) 4.45 to 8.45 MPa (45.38 to 86.17 kgf/cm2 , 645 to 1225 psi)
        150 N (15 kgf, 33.7 lbf) 1.17 to 1.97 MPa 7.30 to 11.30 MPa 7.00 to 11.00 MPa 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi) 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi)
        200 N (20 kgf, 45.0 lbf) 1.87 to 2.67 MPa 7.30 to 11.30 MPa 7.00 to 11.00 MPa 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi) 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi)

        Standard Result

        Pedal Effort Reaction Force Pressure Servo Pressure Master Cylinder Sensor 1 Rear Left Wheel Hydraulic Pressure Rear Right Wheel Hydraulic Pressure
        50 N (5 kgf, 11.2 lbf) 0.00 to 0.64 MPa 1.02 to 5.02 MPa 0.72 to 4.72 MPa 0.72 to 4.72 MPa (7.34 to 48.13 kgf/cm2 , 104 to 684 psi) 0.72 to 4.72 MPa (7.34 to 48.13 kgf/cm2 , 104 to 684 psi)
        100 N (10 kgf, 22.5 lbf) 0.52 to 1.32 MPa 4.75 to 8.75 MPa 4.45 to 8.45 MPa 4.45 to 8.45 MPa (45.38 to 86.17 kgf/cm2 , 645 to 1225 psi) 4.45 to 8.45 MPa (45.38 to 86.17 kgf/cm2 , 645 to 1225 psi)
        150 N (15 kgf, 33.7 lbf) 1.17 to 1.97 MPa 7.30 to 11.30 MPa 7.00 to 11.00 MPa 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi) 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi)
        200 N (20 kgf, 45.0 lbf) 1.87 to 2.67 MPa 7.30 to 11.30 MPa 7.00 to 11.00 MPa 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi) 7.00 to 11.00 MPa (71.38 to 112.17 kgf/cm2 , 1015 to 1595 psi)
      4. Remove the pedal effort gauge and SST.

        (1) Remove the pedal effort gauge and SST, and bleed the brake line.

        Refer to BLEEDING [11/2021 - ]

      5. Inspect the accumulator pressure.

        (1) While fully depressing the brake pedal 4 or 5 times, check that the "ECB Motor Relay" changes to ON once or more.

        Chassis > Brake Booster > Data List 

        Tester Display
        ECB Motor Relay
        Accumulator Pressure

        HINT: 

        Usually the "ECB Motor Relay" is OFF.

        (2) After confirming that the brake booster pump motor stops, check the value output from "Accumulator Pressure".

        Standard Result

        15 to 21 MPa

    2. INSPECT BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY
      1. Check the auxiliary battery voltage.

        Standard Voltage

        11 to 14 V (while the ignition switch is off)

      2. Set a pedal effort gauge and SST.
        GTY976676Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *a Pedal Effort Gauge *b SST (LSPV Gauge)
        *c SST (No. 1 Nipple) - -

        HINT: 

        Simultaneously measure the brake fluid pressure of all 4 wheels, or 2 wheels at a time.

        (1) Set a pedal effort gauge and SST.

        • SST: 09709-29018 
          1. 09709-00060

        (2) Park (P) selected and parking brake applied.

        (3) Clear the DTCs.

        Chassis > Brake Booster > Clear DTCs 

        Chassis > Brake/EPB > Clear DTCs 

        (4) Bleed air from SST (LSPV gauge).

        Refer to BLEEDING [11/2021 - ]

      3. Check operation without brake boost.

        (1) Inspect and adjust the brake pedal height.

        (2) Adjust the brake fluid level of the reservoir so that it is between the MIN line and fluid level support line.

        GTY976382Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *a Fluid Level Support Line
        *b MIN Line

        (3) Select "Motor Deactivate" on the "ECB Utility" screen.

        Chassis > Brake/EPB > Utility 

        Tester Display
        ECB Utility

        (4) Perform "Motor Deactivate" according to the display on the GTS.

        (5) Depress the brake pedal 40 times or more to return all the fluid in the accumulator back to the reservoir.

        HINT: 

        A buzzer may sound due to low accumulator pressure. As this is not a malfunction, continue the procedure.

        (6) Check that the brake pedal is firm.

        (7) Check the values output from "Stroke Sensor" and "Stroke Sensor2" by depressing the brake pedal.

        Chassis > Brake Booster > Data List 

        Tester Display
        Stroke Sensor

        Chassis > Brake/EPB > Data List 

        Tester Display
        Stroke Sensor2

        Standard Result

        Pedal Effort Stroke Sensor Stroke Sensor2 Front Left Wheel Hydraulic Pressure Front Right Wheel Hydraulic Pressure
        200 N (20 kgf, 45.0 lbf) 1.53 to 2.23 V 2.77 to 3.47 V 0.00 to 2.88 MPa (0 to 29.37 kgf/cm2 , 0 to 418 psi) 0.00 to 2.88 MPa (0 to 29.37 kgf/cm2 , 0 to 418 psi)
        500 N (51 kgf, 112.4 lbf) 1.93 to 2.63 V 2.37 to 3.07 V 1.13 to 5.13 MPa (11.52 to 52.31 kgf/cm2 , 164 to 744 psi) 1.13 to 5.13 MPa (11.52 to 52.31 kgf/cm2 , 164 to 744 psi)

        Standard Result

        Pedal Effort Stroke Sensor Stroke Sensor2 Rear Left Wheel Hydraulic Pressure Rear Right Wheel Hydraulic Pressure
        200 N (20 kgf, 45.0 lbf) 1.53 to 2.23 V 2.77 to 3.47 V 0.00 to 2.88 MPa (0 to 29.37 kgf/cm2 , 0 to 418 psi) 0.00 to 2.88 MPa (0 to 29.37 kgf/cm2 , 0 to 418 psi)
        500 N (51 kgf, 112.4 lbf) 1.93 to 2.63 V 2.37 to 3.07 V 1.13 to 5.13 MPa (11.52 to 52.31 kgf/cm2 , 164 to 744 psi) 1.13 to 5.13 MPa (11.52 to 52.31 kgf/cm2 , 164 to 744 psi)

        HINT: 

        Check the performance of the brake booster with master cylinder assembly by comparing the pedal force with the value of the LSPV gauge and each stroke sensor. If there is a problem, determine the state of the brake booster with master cylinder assembly by using these results together with the results from inspecting the brake pedal stroke sensor.

        (8) Remove the pedal effort gauge and SST, and bleed the brake system.

        Refer to BLEEDING [11/2021 - ]

        (9) Check the value output from "Accumulator Pressure".

        Chassis > Brake Booster > Data List 

        Tester Display
        Accumulator Pressure

        Standard Result

        15 to 21 MPa

        (10) Clear the DTCs.

        Chassis > Brake Booster > Clear DTCs 

        Chassis > Brake/EPB > Clear DTCs 

    3. INSPECT STROKE SIMULATOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY)
      1. Check the auxiliary battery voltage.

        Standard Voltage

        11 to 14 V (while the ignition switch is off)

      2. Set a pedal effort gauge.

        (1) Set a pedal effort gauge.

        (2) Park (P) selected and parking brake applied.

        (3) Clear the DTCs.

        Chassis > Brake Booster > Clear DTCs 

        Chassis > Brake/EPB > Clear DTCs 

      3. Check operation with brake boost.

        (1) Depress the brake pedal 4 or 5 times.

        (2) Check the values output from "Stroke Sensor" and "Stroke Sensor2" by depressing the brake pedal.

        Chassis > Brake Booster > Data List 

        Tester Display
        Stroke Sensor

        Chassis > Brake/EPB > Data List 

        Tester Display
        Stroke Sensor2

        Standard Voltage

        Pedal Effort Stroke Sensor Stroke Sensor2
        50 N (5 kgf, 11.2 lbf) 1.21 to 1.91 V 3.09 to 3.79 V
        100 N (10 kgf, 22.5 lbf) 1.43 to 2.13 V 2.87 to 3.57 V
        150 N (15 kgf, 33.7 lbf) 1.63 to 2.33 V 2.67 to 3.37 V
        200 N (20 kgf, 45.0 lbf) 1.68 to 2.38 V 2.62 to 3.32 V
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