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Inspection Procedure

NOTE: When replacing the brake actuator assembly, perform zero point CALIBRATION  .
  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check if the CAN communication system DTC is output (See DIAGNOSIS SYSTEM ).

      Result 

      RESULT CHART

      Condition Proceed to
      DTC is not output A
      DTC is output B

    B: INSPECT CAN COMMUNICATION SYSTEM 

    A: Go to Next Step 

  2. CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED 
    1. Check if the skid control ECU connector is securely connected.

      OK: 

      The connector should be securely connected. 

    NG: CONNECT CONNECTOR TO ECU CORRECTLY 

    OK: Go to Next Step 

  3. CHECK BATTERY 
    1. Check the battery voltage.

      Standard voltage: 

      11 to 14 V 

    NG: CHECK AND REPLACE CHARGING SYSTEM OR BATTERY 

    OK: Go to Next Step 

  4. INSPECT SKID CONTROL ECU (IG1 TERMINAL) 
    1. Disconnect the skid control ECU connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      A36-46 (IG1) - Body ground Engine switch on (IG) 10 to 14 V
    Fig 1: Identifying IG1 Terminal Of Skid Control ECU Connector
    G05250423Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT) 

    OK: Go to Next Step 

  5. INSPECT SKID CONTROL ECU (GND TERMINAL) 
    1. Turn the engine switch off.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      A36-32 (GND1) - Body ground Always Below 1 Ω
      A36-1 (GND2) - Body ground Always Below 1 Ω
    Fig 2: Identifying GND Terminal Of Skid Control ECU Connector
    G05250408Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) 

    OK: Go to Next Step 

  6. INSPECT PARKING BRAKE SWITCH 
    1. Disconnect the parking brake switch connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      1 - Body ground Parking brake switch ON (Switch pin free) Below 1 Ω
      1. Body ground Parking brake switch OFF (Switch pin pushed in) 10 kΩ or higher
      Fig 3: Inspecting Parking Brake Switch
      G05011176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE PARKING BRAKE SWITCH 

    OK: Go to Next Step 

  7. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - PARKING BRAKE SWITCH) 
    1. Disconnect the main body ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      DC-14 (PKB) - A32-1 Always Below 1 Ω
      DC-14 (PKB) - Body ground Always 10 kΩ or higher
    Fig 4: Identifying DC And A32 Main Body ECU Connector
    G05250454Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  8. INSPECT BRAKE FLUID LEVEL WARNING SWITCH 
    1. Remove the reservoir tank cap and strainer.
    2. Disconnect the brake fluid level warning switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      HINT:

      A float is located inside the reservoir. Its position can be changed by increasing or decreasing the level of brake fluid.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      1 - 2 Float up (Switch OFF) 1.9 to 2.1 kΩ
      1 - 2 Float down (Switch ON) Below 1 Ω
      Fig 5: Disconnecting Brake Fluid Level Warning Switch Connector
      G04978087Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      If there is no problem after finishing the above check, adjust the brake fluid level to the MAX level.

    NG: REPLACE BRAKE MASTER CYLINDER RESERVOIR SUB-ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH) 

    OK: Go to Next Step 

  9. CHECK HARNESS AND CONNECTOR (COMBINATION METER - BRAKE FLUID LEVEL WARNING SWITCH) 
    1. Disconnect the combination meter connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      E20-6 (B/LE) - A6-1 (+) Always Below 1 Ω
      E20-6 (B/LE) - Body ground Always 10 kΩ or higher
      A6-2 (E) - Body ground Always Below 1 Ω
    Fig 6: Identifying Combination Meter Connector And Brake Fluid Level Warning Switch Connector
    G05250456Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  10. INSPECT COMBINATION METER ASSEMBLY 
    1. Perform Active Test of the combination meter (meter CPU) using the intelligent tester (See DATA LIST / ACTIVE TEST ).

      OK: 

      The BRAKE warning light turns on or off in accordance with the intelligent tester. 

      HINT:

      • Reinstall the connectors and restore the vehicle to its prior condition before checking the combination meter.
      • If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (See PROBLEM SYMPTOMS TABLE  ).

    NG: REPLACE COMBINATION METER ASSEMBLY 

    OK: REPLACE BRAKE ACTUATOR ASSEMBLY 

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