ELECTRIC PARKING BRAKE SYSTEM SYSTEM DESCRIPTION


  1. SYSTEM DESCRIPTION

    The electric parking brake system controls the parking brake cable by electrically loosening and tightening the cable with the actuator. The main functions are as follows.


    • 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 depressed, the parking brake disengages.

    • When the AUTO function (shift-linked function) is on, parking brake operation is linked with the shift lever, and when the shift lever is moved to P, the parking brake locks. When the shift lever is moved from P to a different position with the brake pedal depressed, the lock releases.

    • When the electric parking brake switch assembly is pulled for 3 seconds or more with the vehicle stopped, the AUTO function (shift-linked function) turns on. When the switch is pressed and held for 3 seconds or more, the AUTO function 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.


    1. The standard parking brake lock/release controls (while vehicle is stopped) are as follows.


      1. The lock control will tighten the parking brake cable to increase tension. The tension will be increased to the target value based on the tilt of the vehicle according to the deceleration sensor (airbag sensor assembly). If the cable tension reaches the target value, the lock control stops tightening the cable and maintains this cable tension.

      2. The release control loosens the cable until the parking brake cable tension reaches a specified value.

    2. When the vehicle is in motion, the parking brake only locks while the electric parking brake switch assembly is pulled up and releases when the switch is released.

  2. COMPONENTS OPERATION


    1. Parking brake ECU assembly


      1. The parking brake ECU assembly operates the parking brake with bracket actuator assembly to lock or release the parking brake according to the shift lever position, signals and conditions through CAN communication, and switch operations from the driver.

    2. Parking brake with bracket actuator assembly


      1. The parking brake with bracket actuator assembly controls the parking brake by tightening and loosening the parking brake cable according to signals from the parking brake ECU assembly.

    3. Tension sensor


      1. The tension sensor is built into the parking brake with bracket actuator assembly and outputs the tension value of the parking brake cable to the parking brake ECU assembly.

    4. Electric parking brake switch assembly


      1. Detects driver switch operations and outputs signals to the parking brake ECU assembly.

    5. Brake system warning light (yellow indicator)


      1. The brake system warning light (yellow indicator) is used by the parking brake ECU assembly and skid control ECU (master cylinder solenoid). If the electric parking brake system is malfunctioning or a problem in another system causes the parking brake function to be limited, this light informs the driver. This light also illuminates for 3 seconds after the engine switch is turned on (IG).

    6. Parking brake indicator light (red)


      1. When the parking brake is locked, the parking brake indicator light (red) illuminates. Also, if the driver attempts to operate the electric parking brake when operation is not possible, the light blinks. The light also blinks when the cable loosens due to an outside influence.

    7. Electric parking brake switch indicator light


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

    8. 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 the system control is not possible, the brake system warning light (yellow indicator) and multi-information display are used to inform the driver. The multi-information display is also used to display cautions.