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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (See INITIALIZATION ).
  1. CHECK DTC 
    1. Check if the ABS, VSC and/or Electronically Controlled Brake DTC is output (See DTC CHECK / CLEAR ).

    Result 

    RESULT CHART

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

    B: REPAIR CIRCUIT INDICATED BY OUTPUT CODE 

    A: Go to next step 

  2. INSPECT 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: REPAIR CAN COMMUNICATION SYSTEM 

    A: Go to next step 

  3. INSPECT MULTIPLEX COMMUNICATION SYSTEM 
    1. Check if the multiplex communication system DTC is output (See DTC CHECK / CLEAR ).

    Result 

    RESULT CHART

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

    B: REPAIR MULTIPLEX COMMUNICATION SYSTEM 

    A: Go to next step 

  4. INSPECT IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED 
    1. Check the skid control ECU connector's connection.

    OK: The connector should be securely connected. 

    NG: CONNECT CONNECTOR TO ECU CORRECTLY 

    OK: Go to next step 

  5. INSPECT BATTERY 
    1. Check the battery voltage.

      Voltage: 11 to 14 V 

    NG: INSPECT CHARGING SYSTEM 

    OK: Go to next step 

  6. INSPECT SKID CONTROL ECU (IG1 TERMINAL) 
    1. Turn the ignition switch on.
    2. Measure the voltage according to the value(s) in the table below.

    Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    S39-7 (IG1) - Body ground Ignition switch on 10 to 14 V

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

    Fig 1: Identifying Skid Control ECU Connector Terminal (IG1 Terminal)
    G05276921Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: Go to next step 

  7. INSPECT SKID CONTROL ECU (GND TERMINAL) 
    1. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    S38-1 (GND1) - Body ground Below 1 Ω
    S39-2 (GND2) - Body ground Below 1 Ω
    S39-1 (GND3) - Body ground Below 1 Ω
    S40-2 (GND4) - Body ground Below 1 Ω
    S40-1 (GND5) - Body ground Below 1 Ω
    S41-4 (GND6) - Body ground Below 1 Ω
    Fig 2: Inspecting Skid Control ECU Connector Terminal (GND Terminal)
    G05276879Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

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

    OK: Go to next step 

  8. READ VALUE OF INTELLIGENT TESTER (PARKING BRAKE SWITCH) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch on.
    3. Select the DATA LIST mode on the intelligent tester.

      ABS/VSC/TRAC: 

      MEASUREMENT ITEM NORMAL CONDITION CHART

      Item (Display) Measurement Item/Range (Display) Normal Condition
      PARKING BRAKE SW Parking brake switch/ON or OFF ON: Parking brake pedal depressed
      OFF: Parking brake pedal released
    4. Using the intelligent tester, check the input of switch operation when the parking brake pedal is operated.

      OK: When the parking brake pedal is operated, the display changes as shown above. 

    NG: GO TO step   10 

    OK: Go to next step 

  9. INSPECT COMBINATION METER ASSEMBLY 
    1. Check the combination meter assembly (See HOW TO PROCEED WITH TROUBLESHOOTING ).

      HINT:

      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 SKID CONTROL ECU 

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

    Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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
    G05202768Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    NG: REPLACE PARKING BRAKE SWITCH 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (BETWEEN PARKING BRAKE SWITCH AND SKID CONTROL ECU) 
    1. Disconnect the skid control ECU connector S40 and parking brake switch connector.
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Specified Condition
    S40-14 (PKB) - P6-1 Below 1 Ω
    S40-14 (PKB) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Identifying Skid Control ECU Connector S40 And Parking Brake Switch Connector
    G05276927Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

    OK: REPLACE SKID CONTROL ECU 

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