ELECTRONICALLY CONTROLLED BRAKE SYSTEM Skid Control Buzzer Circuit

DESCRIPTION

A buzzer sounds to alert the driver when the vehicle-to-vehicle distance becomes less than the set value (for vehicles with a dynamic radar cruise control system).

INSPECTION PROCEDURE

PROCEDURE

1. Click here

   CHECK BUZZER OPERATION

   
   

   1. Confirm problem symptoms of the skid control buzzer according to the customer problem analysis.

      Result
      Result Proceed to Buzzer does not sound A Buzzer sounds constantly B

   
   
   • AClick here
   • BClick here
2. Click here

   PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SKID CONTROL BUZZER)

   
   

   1. Connect the intelligent tester to the DLC3.

   2. Turn the power switch on (IG).

   3. Select the Active Test on the intelligent tester (Click here).

      Table 1. ABS/VSC/TRC

      Tester Display	Test Part	Control Range	Diagnostic Note
      DSS Signal Buzzer	Skid control buzzer	Buzzer ON/OFF	Buzzer can be heard

   4. Check that the buzzer sounds/stops when turning the skid control buzzer on/off using the intelligent tester.

      Result
      Result Proceed to Buzzer does not sound A Buzzer sounds/stops B

      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step (Click here).

   
   
   • AClick here
   • BClick here
3. Click here

   INSPECT SKID CONTROL BUZZER (POWER SOURCE TERMINAL)

   
   
   1. 

      Turn the power switch off.

   2. Disconnect the skid control buzzer connector.

   3. Turn the power switch on (IG).

   4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition H24-2 (IG1) - Body ground Power switch on (IG) 11 to 14 V

      Table 2. Text in Illustration

      *a	Front view of wire harness connector (to Skid Control Buzzer)

   
   
   • OKClick here
   • NGClick here
4. Click here

   INSPECT SKID CONTROL BUZZER

   
   
   1. 

      Turn the power switch off.

   2. Connect a negative (-) lead from the battery to terminal 1 (BZ), and a positive (+) lead to terminal 2 (IG1) of the skid control buzzer, and then check that the buzzer sounds.

      OK
      The skid control buzzer sounds.

      Table 3. Text in Illustration

      *a	Component without harness connected (Skid Control Buzzer)

      Result
      Result Proceed to OK A NG (for LHD) B NG (for RHD) C

   
   
   • AClick here
   • BClick here
   • CClick here
5. Click here

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

   
   

   1. Disconnect the skid control ECU connector 2 minutes after the power switch is turned off.

      Tip:

      Do not open/close the driver door within 2 minutes after the power switch is turned off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition A61-13 (BZ) - H24-1 (BZ) Always Below 1 Ω A61-13 (BZ) - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NGClick here
6. Click here

   INSPECT SKID CONTROL ECU (GND TERMINAL)

   
   
   1. 

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

      Standard Resistance
      Tester Connection Condition Specified Condition A61-28 (GND) - Body ground Always Below 1 Ω A61-27 (GND2) - Body ground Always Below 1 Ω A61-26 (GND3) - Body ground Always Below 1 Ω A61-25 (GND4) - Body ground Always Below 1 Ω A61-24 (GND5) - Body ground Always Below 1 Ω A61-23 (GND6) - Body ground Always Below 1 Ω

      Table 4. Text in Illustration

      *a	Front view of wire harness connector (to Skid Control ECU)

      Result
      Result Proceed to OK (for LHD) A OK (for RHD) B NG C

      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (Click here).

   
   
   • AClick here
   • BClick here
   • CClick here
7. Click here

   INSPECT SKID CONTROL ECU

   
   

   1. Disconnect the skid control ECU connector.

   2. Check that the skid control buzzer operation.

      Result
      Result Proceed to Buzzer stops (for LHD) A Buzzer stops (for RHD) B Buzzer sounds constantly C

      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (Click here).

   
   
   • AClick here
   • BClick here
   • CClick here
8. Click here

   REPLACE SKID CONTROL BUZZER

   
   

   1. Reconnect the skid control ECU connector.

   2. Replace the skid control buzzer (Click herefor LHD orClick herefor RHD).

   3. Check that the skid control buzzer operation.

      Result
      Result Proceed to Buzzer stops A Buzzer sounds constantly B

      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (Click here).

   
   
   • AClick here
   • BClick here
9. Click here

   CHECK IF CONNECTOR IS SECURELY CONNECTED

   
   

   1. Gently jiggle the connectors and wire harnesses and check the skid control buzzer operation.

      Result
      Result Proceed to Buzzer stops A Buzzer sounds constantly B

      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (Click here).

   
   
   • AClick here
   • BClick here
10. Click here

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDERClick here

11. Click here

    END

12. Click here

    CHECK FOR INTERMITTENT PROBLEMSClick here

13. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

14. Click here

    REPLACE SKID CONTROL BUZZERClick here

15. Click here

    REPLACE SKID CONTROL BUZZERClick here

16. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR

17. Click here

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDERClick here

18. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)