ELECTRIC PARKING BRAKE SYSTEM Electric Parking Brake does not Operate

WIRING DIAGRAM

B005B8CE04

CAUTION / NOTICE / HINT

Note


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

  • Before disconnecting connectors or fuses, turn the engine switch off and wait 20 seconds or more.

  • When replacing the parking brake ECU assembly, operate the electric parking brake switch (integration control and panel assembly), as the parking brake indicator light (red) blinks when the engine switch is first turned on (IG).

Tech Tips

The condition may be that the electric parking brake is operating normally but the meter parking brake indicator light (red) is malfunctioning.

PROCEDURE


  1. VEHICLE OPERATION CHECK


    1. Start the engine and move the shift lever to D. Then depress the brake pedal and pull the electric parking brake switch (integration control and panel assembly) to the lock side for 1 second. Check the parking brake indicator light (red) condition.

    2. Release the brake pedal and check that the vehicle does not move.

    3. Depress the brake pedal and push the electric parking brake switch (integration control and panel assembly) to the release side for 1 second. Check the parking brake indicator light (red) condition.

    4. Release the brake pedal and check that the vehicle moves.

      Result
      Result Proceed to
      Lock and release control is normal; parking brake indicator light (red) is off or is blinking A
      Lock and release control is malfunctioning; parking brake indicator light (red) is illuminated or off depending on switch operation B
      Lock and release control is malfunctioning; parking brake indicator light (red) is off or is blinking C

    B

    INSPECT REAR BRAKE

    C

    CHECK HARNESS AND CONNECTOR (BECU CIRCUIT) Click here

    A

  2. PERFORM ACTIVE TEST USING GTS (PKB LIGHT)


    1. Turn the engine switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the engine switch on (IG) and the GTS on.

    4. Enter the following menus: Chassis / Electric Parking Brake / Active Test.

    5. Check the condition of the parking brake indicator light (red) by operating the GTS.


      Chassis > Electric Parking Brake > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      PKB Light Parking brake indicator light (red) ON or OFF

      • Vehicle stopped

      • Engine switch on (IG)

      • Parking brake released

      Chassis > Electric Parking Brake > Active Test
      Tester Display
      PKB Light
      OK
      Indicator light turns on when operating the GTS.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE PARKING BRAKE ECU ASSEMBLY Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (PARKING BRAKE ECU ASSEMBLY - COMBINATION METER ASSEMBLY)


    1. Turn the engine switch off.

    2. Disconnect the Q24 parking brake ECU assembly connector.

    3. Disconnect the I10 combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition

      Q24-4 (TX) - I10-5 (EPB)*

      		Always Below 1 Ω

      Q24-4 (TX) or I10-5 (EPB)*- Body ground

      		 Always 10 kΩ or higher

      Tech Tips

      *: Stands for electric parking brake

      Result
      Proceed to
      OK
      NG

    OK

    GO TO METER / GAUGE SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. CHECK HARNESS AND CONNECTOR (BECU CIRCUIT)


    1. Turn the engine switch off.

    2. B0057QUC09
      *a

      Front view of wire harness connector

      (to Parking Brake ECU Assembly)

      Disconnect the parking brake ECU assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Q24-3 (BECU) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG (w/o Stop and Start System)
      NG (w/ Stop and Start System)

    NG (w/o Stop and Start System)

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG (w/ Stop and Start System)

    CHECK HARNESS AND CONNECTOR (PARKING BRAKE ECU ASSEMBLY - ENGINE STOP AND START ECU) Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (BATTERY - PARKING BRAKE ECU ASSEMBLY)


    1. Turn the engine switch off.

    2. B0057QUC10
      *a

      Front view of wire harness connector

      (to Parking Brake ECU Assembly)

      Disconnect the parking brake ECU assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Q24-5 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE PARKING BRAKE ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. CHECK HARNESS AND CONNECTOR (PARKING BRAKE ECU ASSEMBLY - ENGINE STOP AND START ECU)


    1. Turn the engine switch off.

    2. Disconnect the Q24 parking brake ECU assembly connector.

    3. Disconnect the I57 engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q24-3 (BECU) - I57-23 (B11) Always Below 1 Ω
      Q24-3 (BECU) or I57-23 (B11) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STOP AND START SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR