ELECTRONICALLY CONTROLLED BRAKE SYSTEM Skid Control Buzzer Circuit

DESCRIPTION

The skid control buzzer sounds while the accumulator pressure is abnormally low or an abnormality causing low fluid pressure occurs.

If the accumulator pressure is abnormally low, or an abnormal fluid pressure drop is occurring, the skid control buzzer sounds.

WIRING DIAGRAM

A01H14ME05

INSPECTION PROCEDURE

Note

When replacing the skid control ECU, perform the following operations:


  • Initialization of linear solenoid valve and calibration Click here

  • Yaw rate and acceleration sensor zero point calibration Click here

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (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.

      ABS/VSC/TRAC:
      Tester Display Test Part Control Range Diagnostic Note
      Buzzer 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 Proceed to
      Buzzer does not sound or sounds constantly A
      Buzzer sounds/stops for LHD B
      for RHD C

      Tech Tips

      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 Click here.


    B

    REPLACE SKID CONTROL ECU Click here

    C

    REPLACE SKID CONTROL ECU Click here

    A

  2. INSPECT SKID CONTROL BUZZER (POWER SOURCE TERMINAL)


    1. A01GYULE28

      Disconnect the L2 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 Switch Condition Specified Condition
      L2-2 - Body ground Power switch ON (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

  3. INSPECT SKID CONTROL BUZZER


    1. A01GXS7E03

      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.

    NG

    REPLACE SKID CONTROL BUZZER ASSEMBLY Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - SKID CONTROL BUZZER)


    1. A01H217E03

      Disconnect the A19 ECU connector.

    2. Disconnect the L2 buzzer connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      A19-22 (BZ) - L2-1 Always Below 1 Ω
      A19-22 (BZ) - Body ground Always 10 kΩ or higher
      A19-41 (VBZ) - L2-2 Always Below 1 Ω
      A19-41 (VBZ) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND)


    1. A01H1MKE17

      Disconnect the A19 and A21 ECU connectors.

    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      A19-1 (GND) - Body ground Always Below 1 Ω
      A21-1 (GND4) - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      NG A
      OK for LHD B
      for RHD C

      Tech Tips

      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 Click here.


    B

    REPLACE SKID CONTROL ECU Click here

    C

    REPLACE SKID CONTROL ECU Click here

    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR