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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 system DTC is output (see DTC CHECK / CLEAR  ).

      Result 

      RESULT

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

    B: REPAIR CIRCUIT INDICATED BY OUTPUT CODE (See  DIAGNOSTIC TROUBLE CODE CHART   ) 

    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

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

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

    A: GO TO Next Step 

  3. INSPECT MULTIPLEX COMMUNICATION SYSTEM 
    1. Check if the multiplex communication system DTC is output (see DIAGNOSIS SYSTEM ).

      Result 

      RESULT

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

    B: REPAIR MULTIPLEX COMMUNICATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    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 is securely connected. 

    NG: CONNECT CONNECTOR TO ECU CORRECTLY  (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE )

    OK: GO TO Next Step 

  5. INSPECT BATTERY 
    1. Check the battery voltage.

      Standard voltage: 

      10 to 14 V 

    NG: INSPECT CHARGING SYSTEM  (See ON-VEHICLE INSPECTION )

    OK: GO TO Next Step 

  6. CHECK WIRE HARNESS (SKID CONTROL ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the A13 and A15 ECU connectors.
    2. Turn the power switch ON (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A13-16 (IG1) - Body ground Power switch ON (IG) 10 to 14 V
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A13-1 (GND) - Body ground Below 1 Ω
      A15-1 (GND4) - Body ground Below 1 Ω
      Fig 1: Identifying A13 And A15 Connectors Terminals
      G05306004Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: GO TO Next Step 

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

      Skid control ECU: 

      DATA LIST

      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 replaced
    4. Using the intelligent tester, check the input of switch operation when the parking brake switch is operated.

      OK: 

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

    NG:  GO TO step  9

    OK: GO TO Next Step 

  8. INSPECT COMBINATION METER ASSEMBLY 
    1. Check the combination meter (see INITIALIZATION ).

      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.

    NG: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

    OK: REPLACE SKID CONTROL ECU 

  9. 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 

      TESTER CONNECTION SPECIFIED CONDITION

      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

      Result 

      RESULT

      Result Proceed to
      OK A
      NG B
      Fig 2: Inspecting Parking Brake Switch
      G05306007Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: REPLACE PARKING BRAKE SWITCH 

    A: GO TO Next Step 

  10. CHECK WIRE HARNESS (PARKING BRAKE SWITCH - MAIN BODY ECU RH) 
    1. Disconnect the DL ECU RH connector.
    2. Disconnect the A33 switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      DL-10 (PKB) - A33-1 Below 1 Ω
      DL-10 (PKB) - Body ground 10 kΩ or higher
      Fig 3: Identifying DL And A33 Connectors Terminals
      G05306008Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  11. CHECK WIRE HARNESS (SKID CONTROL ECU - MAIN BODY ECU RH) 
    1. Disconnect the A15 ECU connector.
    2. Disconnect the L67 ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A15-23 (PKB) - L67-18 (PKBO) Below 1 Ω
      A15-23 (PKB) - Body ground 10 kΩ or higher
      Fig 4: Identifying A15 And L67 Connectors Terminals
      G05306009Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU RH 

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