VEHICLE STABILITY CONTROL SYSTEM Brake Warning Light Remains ON

DESCRIPTION

The skid control ECU is connected to the combination meter via the CAN and multiplex communication systems.

If any of the following is detected, the brake warning light remains on:


WIRING DIAGRAM

A015ZD1E03

INSPECTION PROCEDURE

Note

When replacing the brake actuator assembly, perform zero point calibration and store system information Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication system DTC is output Click here.

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

    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    A

  2. CHECK MULTIPLEX COMMUNICATION SYSTEM


    1. Check if a multiplex communication system DTC is output Click here.

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

    B

    INSPECT MULTIPLEX COMMUNICATION SYSTEM Click here

    A

  3. CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED


    1. Check if the skid control ECU connector is securely connected.

      OK
      The connector is securely connected.

    NG

    CONNECT CONNECTOR TO ECU CORRECTLY

    OK

  4. CHECK BATTERY


    1. Check the battery voltage.

      Standard Voltage
      11 to 14 V

    NG

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (for 2UR-GSE) Click here

    OK

  5. INSPECT SKID CONTROL ECU (IG1 TERMINAL)


    1. A01613JE47
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Disconnect the skid control ECU connector.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A62-34 (IG1) - Body ground Engine switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

    OK

  6. INSPECT SKID CONTROL ECU (GND1 TERMINAL)


    1. A01613JE46
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Turn the engine switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A62-1 (GND1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

    OK

  7. READ VALUE USING INTELLIGENT TESTER (PARKING BRAKE SWITCH)


    1. Reconnect the skid control ECU connector.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the engine switch on (IG).

    4. Select the Data List on the intelligent tester Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Parking Brake SW Parking brake switch / ON or OFF

      ON: Parking brake applied

      OFF: Parking brake released

      		 -

    5. Using the intelligent tester, check the switch condition on the intelligent tester changes according to parking brake operation.

      OK
      The intelligent tester displays ON or OFF according to parking brake pedal operation.

    NG

    INSPECT PARKING BRAKE SWITCH Click here

    OK

  8. INSPECT BRAKE FLUID LEVEL WARNING SWITCH


    1. A015YY7E01
      Text in Illustration
      *1

      Component without harness connected

      (Brake Fluid Level Warning Switch)

      Turn the engine switch off.

    2. Remove the reservoir filler cap and strainer.

    3. Disconnect the brake fluid level warning switch connector.

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

      Tech Tips

      A float is located inside the reservoir. Its position can be changed by increasing or decreasing the level of brake fluid.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 (+) - 2 (E) Brake fluid level warning switch OFF (Float up) 1.9 to 2.1 kΩ
      1 (+) - 2 (E) Brake fluid level warning switch ON (Float down) Below 1 Ω

      Tech Tips

      If there is no problem after finishing the above check, adjust the brake fluid level to the MAX level.


    NG

    REPLACE BRAKE MASTER CYLINDER RESERVOIR SUB-ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH)

    OK

  9. CHECK HARNESS AND CONNECTOR (COMBINATION METER - BRAKE FLUID LEVEL WARNING SWITCH)


    1. A0161SQE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter)
      *2

      Front view of wire harness connector

      (to Brake Fluid Level Warning Switch)

      Disconnect the combination meter connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      J35-15 (SW) - A16-1 (+) Always Below 1 Ω
      J35-15 (SW) - Body ground Always 10 kΩ or higher
      A16-2 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. INSPECT COMBINATION METER ASSEMBLY


    1. Perform the Active Test of the combination meter (meter CPU) using the intelligent tester Click here.

    2. Check the combination meter.

      Tech Tips

      Reinstall the connectors and restore the vehicle to its prior condition before checking the combination meter.

      OK
      The brake warning light turns on or off in accordance with the intelligent tester operation.

      Tech Tips

      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.


    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  11. INSPECT PARKING BRAKE SWITCH


    1. A015YI4E01

      Turn the engine switch off.

    2. Disconnect the parking brake switch connector.

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

      Standard Resistance
      Tester Connection Switch 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

    NG

    REPLACE PARKING BRAKE SWITCH Click here

    OK

  12. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - PARKING BRAKE SWITCH)


    1. A015Z9YE07
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)
      *2

      Front view of wire harness connector

      (to Parking Brake Switch)

      Disconnect the skid control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A62-29 (PKB) - A25-1 Always Below 1 Ω
      A62-29 (PKB) - Body ground Always 10 kΩ or higher

      Tech Tips

      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.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here