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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (see INITIALIZATION  ).
  1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (SKID CONTROL BUZZER) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the power switch ON (IG) and turn the intelligent tester main switch on.
    3. Select ACTIVE TEST mode on the intelligent tester.

      Skid control ECU: 

      DATA LIST

      Item (Display) Vehicle Condition / Test Details Diagnostic Note
      BUZZER Turns skid control buzzer ON / OFF Buzzer can be heard
    4. Check that the buzzer sounds/stops when turning the skid control buzzer on/off by using the intelligent tester.

      Result 

      RESULT

      Condition Proceed to
      Buzzer does not sound or sounds constantly A
      Buzzer sounds/stops B

      HINT:

      If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE ", refer back to the table and proceed to the next step.

    B: REPLACE SKID CONTROL ECU (See  REMOVAL   ) 

    A: GO TO Next Step 

  2. INSPECT SKID CONTROL BUZZER (POWER SOURCE TERMINAL) 
    1. Disconnect the K11 buzzer connector.
    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
      K11-2 - Body ground Power switch ON (IG) 10 to 14 V
      Fig 1: Identifying K11 Connector Terminals
      G05306016Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

    OK: GO TO Next Step 

  3. INSPECT SKID CONTROL BUZZER 
    1. Disconnect the skid control buzzer connector.
    2. Apply battery negative voltage to terminal 1, and battery positive voltage to terminal 2 of the skid control buzzer, and then check that the buzzer sounds.

      OK: 

      Skid control buzzer sounds. 

      Fig 2: Inspecting Skid Control Buzzer
      G05306017Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SKID CONTROL BUZZER 

    OK: GO TO Next Step 

  4. CHECK WIRE HARNESS (SKID CONTROL ECU - SKID CONTROL BUZZER) 
    1. Disconnect the A13 ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A13-6 (BZ) - K11-1 Below 1 Ω
      A13-6 (BZ) - Body ground 10 kΩ or higher
      A13-22 (VBZ) - K11-2 Below 1 Ω
      A13-22 (VBZ) - Body ground 10 kΩ or higher
      Fig 3: Identifying A13 And K11 Connectors Terminals
      G05306018Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  5. CHECK WIRE HARNESS (SKID CONTROL ECU - BODY GROUND) 
    1. Disconnect the A13 and A15 ECU connectors.
    2. 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

      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.

      Fig 4: Identifying A13 And A15 Connectors Terminals
      G05305962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: REPLACE SKID CONTROL ECU (See  REMOVAL   )