ELECTRIC PARKING BRAKE SYSTEM SYSTEM DESCRIPTION


  1. SYSTEM DESCRIPTION


    1. The electric parking brake system electronically controls the parking brake lock and release operations using actuators. The main functions are as follows.


        Functions when vehicle stopped:

      • When the electric parking brake switch assembly is pulled, the parking brake engages. When the electric parking brake switch assembly is pushed with the brake pedal or accelerator pedal depressed or the shift lever in P, the parking brake disengages.

      • When the AUTO function (shift-linked function) is on, the operation of the parking brake is linked with the shift lever, and when the shift lever is moved to P, the parking engages. When the shift lever is moved from P to any other position with the brake pedal depressed, the parking brake disengages.

      • When the electric parking brake switch assembly is pulled and held to the lock side for 5 seconds or more with the vehicle stopped, the AUTO function (shift-linked function) is turned on (AUTO indicator light illuminates). When the switch is pushed and held to the release side for 5 seconds or more, the AUTO function (shift-linked function) is turned off (AUTO indicator light turns off).

      • If a malfunction occurs in the electric parking brake switch assembly when the AUTO function (shift-linked function) is off, the AUTO function (shift-linked function) automatically operates to ensure operability.

        Tech Tips

        Only the release operation functions.


        Other supplementary functions:

      • When any of the following conditions are met while the brake hold function is operating (vehicle is stopped) and the brake pedal is not depressed, the parking brake automatically engages.


        • The driver door is opened

        • The driver seat belt is unfastened

        • The brake hold function is continuously operated for 3 minutes

      • If the parking brake is engaged by other supplementary functions, the parking brake automatically disengages when all of the following conditions are met:


        • The driver door is closed.

        • The driver seat belt is fastened

        • The accelerator pedal is depressed

      • Tech Tips

        If the electric parking brake system malfunctions while the brake hold function is operating (vehicle is stopped), the parking brake automatically engages.

        When starting off the vehicle, it is necessary to push the electric parking brake switch assembly and hold to the release side to disengage the parking brake.


        Emergency response function:

      • When the vehicle is being driven, the parking brake only engages while the electric parking brake switch assembly is being pulled to the lock side and disengages the parking brake when the switch is released.

  2. COMPONENTS FUNCTION


    1. Skid control ECU (brake actuator assembly)


      1. Operates the parking brake actuator assembly to engage or disengage the parking brake according to electric parking brake switch assembly operation, the shift lever position and signals received via CAN communication.

    2. Parking brake actuator assembly:


      1. Operates the parking brake motor according to commands from the skid control ECU (brake actuator assembly), generates the necessary torque to operate the rear brake calipers.

    3. Rear brake caliper:


      1. Convents the rotary torque generated by the parking brake actuator assembly into a linear force to push the rear brake pads against the disc to generate braking force. When the parking brake motor (parking brake actuator assembly) is stopped, the current force is maintained due to screw friction.

    4. Electric parking brake switch assembly:


      1. Detects switch operations and outputs signals to the skid control ECU (brake actuator assembly).

    5. Brake system warning light (yellow):


      1. The brake system warning light illuminates (yellow) if the electric parking brake system is malfunctioning or a problem in another system causes the parking brake function to be limited.

    6. Parking brake indicator light (red):


      1. The parking brake indicator light illuminates (red) when the parking brake is engaged and turns off when the parking brake is disengaged. Also, if the driver attempts to operate the electric parking brake when operation is not possible or parking force is insufficient, the light blinks.

    7. Electric parking brake switch indicator light:


      1. The electric parking brake switch indicator light in the electric parking brake switch assembly illuminates when the parking brake is locked and turns off when the parking brake is released.

    8. AUTO indicator light:


      1. The AUTO indicator light in the electric parking brake switch assembly informs the driver of whether AUTO function (shift-linked function) control is possible.

        AUTO function (shift-linked function) on: Illuminates, AUTO function (shift-linked function) off: Turns off

    9. Multi-information display:


      1. Displays a message when the AUTO function (shift-linked function) ON/OFF setting is changed.

      2. If a malfunction occurs in the electric parking brake system and system control is not possible, the brake system warning light illuminates (yellow) and a warning message is displayed on the multi-information display to inform the driver.