Skid Control Buzzer Circuit

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: Skid Control Buzzer Circuit
- 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).

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
When replacing the brake booster with master cylinder (skid control ECU), perform initialization and calibration of the linear solenoid valve Initialization.

PROCEDURE

1. CHECK BUZZER OPERATION

(a) Confirm problem symptoms of the skid control buzzer according to the customer problem analysis.

Result:

B -- INSPECT SKID CONTROL ECU
A -- Continue to next step.

2. PERFORM ACTIVE TEST USING TECHSTREAM (SKID CONTROL BUZZER)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Select the Active Test on the Techstream Data List / Active Test.

ABS/VSC/TRAC

(d) Check that the buzzer sounds/stops when turning the skid control buzzer on/off using the Techstream.

Result:

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

B -- CHECK FOR INTERMITTENT PROBLEMS How To Proceed With Troubleshooting
A -- Continue to next step.

3. INSPECT SKID CONTROL BUZZER (POWER SOURCE TERMINAL)

(a) Turn the power switch off.

(b) Disconnect the skid control buzzer connector.

(c) Turn the power switch on (IG).

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

Standard Voltage:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.

4. INSPECT SKID CONTROL BUZZER

(a) Turn the power switch off.

(b) 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.

Text in Illustration

NG -- REPLACE SKID CONTROL BUZZER Removal
OK -- Continue to next step.

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

(a) Disconnect the skid control ECU connector 2 minutes after the power switch is turned off.

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

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

Standard Resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. INSPECT SKID CONTROL ECU (GND TERMINAL)

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

Standard Resistance:

Text in Illustration

HINT
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 Problem Symptoms Table.

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

OK -- REPLACE BRAKE BOOSTER WITH MASTER CYLINDER Removal

7. INSPECT SKID CONTROL ECU

(a) Disconnect the skid control ECU connector.

(b) Check that the skid control buzzer operation.

Result:

HINT
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 Problem Symptoms Table.

B -- REPLACE SKID CONTROL BUZZER

A -- REPLACE BRAKE BOOSTER WITH MASTER CYLINDER Removal

8. REPLACE SKID CONTROL BUZZER

(a) Reconnect the skid control ECU connector.

(b) Replace the skid control buzzer Removal.

(c) Check that the skid control buzzer operation.

Result:

HINT
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 Problem Symptoms Table.

B -- CHECK IF CONNECTOR IS SECURELY CONNECTED

A -- END

9. CHECK IF CONNECTOR IS SECURELY CONNECTED

(a) Gently jiggle the connectors and wire harnesses and check the skid control buzzer operation.

Result: