VEHICLE STABILITY CONTROL SYSTEM Brake Warning Light Remains ON

DESCRIPTION

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

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


WIRING DIAGRAM

A01IQJRE01

INSPECTION PROCEDURE

Note


  • When replacing the skid control ECU (brake actuator assembly), perform the engine variant learning Click here.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


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

      Result
      Result Proceed to
      CAN communication system DTC is not output. A
      CAN communication system DTC is output. B

    B

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    A

  2. 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

  3. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)


    1. Turn the ignition switch off.

    2. Disconnect the skid control ECU connector.

    3. A01ITVSE27
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)
      *2 for AD Series Engine, 1WW
      *3 for ZR Series Engine

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A52 or A54-28 (IG1) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (w/o Stop and Start System) B
      NG (w/ Stop and Start System) C

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    C

    INSPECT STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT) Click here

    A

  4. CHECK HARNESS AND CONNECTOR (GND1, GND2 TERMINAL)


    1. Turn the ignition switch off.

    2. Disconnect the skid control ECU connector.

    3. A01ITVSE28
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)
      *2 for AD Series Engine, 1WW
      *3 for ZR Series Engine

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A52 or A54-4 (GND1) - Body ground Always Below 1 Ω
      A52 or A54-1 (GND2) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. READ VALUE USING INTELLIGENT TESTER (PARKING BRAKE SW)


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    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 input of switch operation when the parking brake is operated.

      OK
      When the parking brake is operated, the display changes as shown above.

    NG

    INSPECT PARKING BRAKE SWITCH Click here

    OK

  6. INSPECT BRAKE FLUID LEVEL WARNING SWITCH


    1. A01IT17E01
      Text in Illustration
      *1

      Component without harness connected

      (Brake Fluid Level Warning Switch)
      *2 for LHD
      *3 for RHD

      Remove the reservoir filler cap and strainer.

    2. Disconnect the brake fluid level warning switch connector.

    3. 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) Switch off (Float up) 1.9 to 2.1 kΩ
      1 (+) - 2 (E) 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 Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (BRAKE FLUID LEVEL WARNING SWITCH - COMBINATION METER/BODY GROUND)


    1. A01IQPQE03
      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. Disconnect the brake fluid level warning switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H62-10 (SW) - A13-1 (+) Always Below 1 Ω
      H62-10 (SW) - Body ground Always 10 kΩ or higher
      A13-2 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. INSPECT COMBINATION METER


    1. Perform the Active Test of the combination meter to check the brake warning light using the intelligent tester Click here.

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

      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.


    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  9. INSPECT PARKING BRAKE SWITCH


    1. Turn the ignition switch off.

    2. Remove the parking brake switch Click here.

    3. A01ITS9E01
      Text in Illustration
      *1

      Component without harness connected

      (Parking Brake Switch)

      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

      Parking brake switch OFF

      (Switch pin pushed in)

      		 10 kΩ or higher

    NG

    REPLACE PARKING BRAKE SWITCH Click here

    OK

  10. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - PARKING BRAKE SWITCH)


    1. Disconnect the main body ECU connector.

    2. Disconnect the parking brake switch connector.

    3. A01IR5PE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Main Body ECU (Instrument Panel junction Block))
      *2

      Front view of wire harness connector

      (to Parking Brake Switch)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      DC-5 (PKB) - H17-1 Always Below 1 Ω
      DC-5 (PKB) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)