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Inspection Procedure

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

      Result 

      RESULT REFERENCE TABLE

      Condition Proceed to
      CAN communication system DTC is not output A
      CAN communication system DTC is output B

    B: INSPECT CAN COMMUNICATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    A: Go to Next Step 

  2. CHECK MULTIPLEX COMMUNICATION SYSTEM 
    1. Check if a multiplex communication system DTC is output (See DTC CHECK/CLEAR ).

      Result 

      RESULT REFERENCE TABLE

      Condition Proceed to
      Multiplex communication system DTC is not output A
      Multiplex communication system DTC is output B

    B: INSPECT MULTIPLEX COMMUNICATION SYSTEM  (See DTC CHECK/CLEAR )

    A: Go to Next Step 

  3. CHECK CONNECTOR CONNECTION CONDITION (SKID CONTROL ECU) 
    1. Check if the skid control ECU connector is securely connected.

      OK: 

      The connector is securely connected. 

    NG: REPAIR OR REPLACE CONNECTOR (SKID CONTROL ECU CONNECTION) 

    OK: Go to Next Step 

  4. CHECK BATTERY 
    1. Check the battery voltage.

      Standard voltage: 

      11 to 14 V 

    NG: CHECK AND REPLACE CHARGING SYSTEM OR BATTERY  (See ON-VEHICLE INSPECTION )

    OK: Go to Next Step 

  5. INSPECT SKID CONTROL ECU (IG1 TERMINAL) 
    1. Disconnect the skid control ECU connector.
    2. Turn the ignition switch to the ON position.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S1 - 46 (IG1) - Body ground Ignition switch ON 10 to 14 V
      Fig 1: Identifying Skid Control ECU (IG1 Terminal)
      G05272747Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to Next Step 

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

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S1 - 32 (GND1) - Body ground Always Below 1 Ω
      S1 - 1 (GND2) - Body ground Always Below 1 Ω
      Fig 2: Identifying Skid Control ECU (GND Terminal)
      G05272706Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to Next Step 

  7. 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      P6-1 - Body ground Parking brake switch ON (Switch pin free) Below 1 Ω
      P6-1 - Body ground Parking brake switch OFF (Switch pin pushed in) 10 kΩ or higher
      Fig 3: Identifying Parking Brake Switch
      G05272757Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE PARKING BRAKE SWITCH  (See DISASSEMBLY )

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - PARKING BRAKE SWITCH) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S1 - 28 (PKB) - P6-1 Always Below 1 Ω
      S1 - 28 (PKB) - Body ground Always 10 kΩ. or higher
      Fig 4: Identifying Skid Control ECU & Parking Brake Switch Connector Terminal
      G05272758Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - PARKING BRAKE SWITCH) 

    OK: Go to Next Step 

  9. 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      B1-1 - B1-2 Float up (Switch OFF) 10 kΩ or higher
      B1-1 - B1-2 Float down (Switch ON) Below 1 Ω
      Fig 5: Identifying Brake Fluid Level Warning Switch
      G05272759Courtesy 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 ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH)  (See REMOVAL )

    OK: Go to Next Step 

  10. 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      C9-8 - B1-1 Always Below 1 Ω
      C9-8 - Body ground Always 10 kΩ or higher
      B1-1 - Body ground Always Below 1 Ω
      Fig 6: Identifying Combination Meter & Brake Fluid Level Warning Switch Connector
      G05272760Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  11. INSPECT COMBINATION METER ASSEMBLY 
    1. Connect the intelligent tester to the DLC3.
    2. Perform Active Test of the combination meter (meter CPU) using the intelligent tester (See DATA LIST/ACTIVE TEST ).

      OK: 

      The BRAKE warning light blinks 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  (See REMOVAL )

    OK: REPLACE BRAKE ACTUATOR ASSEMBLY  (See REMOVAL  )