AIRBAG SYSTEM > SYSTEM DESCRIPTION

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GENERAL

  1. FRONTAL COLLISION

    1. The driver airbag, front passenger airbag, knee airbag and SRS seat cushion airbag are designed to supplement seat belts in the event of a front collision in order to help reduce shock to the head, chest and knees of the driver and front passenger.

    2. Frontal collisions are detected by the center airbag sensor and two front airbag sensors. The driver airbag, front passenger airbag, knee airbag, SRS seat cushion airbag and seat belt pretensioners then operate simultaneously.

  2. SIDE COLLISION

    1. The front seat side airbag and curtain shield airbag are designed to help reduce shock to the driver, front passenger and rear outer passengers in the event of a side collision.

    2. Side collisions are detected by the side airbag sensor (for front side) installed in the bottom of the front door and the side airbag sensor (for rear side) installed in the bottom of the rear pillar.

    3. Front side collisions are detected by the side airbag sensor (for front side), causing the front seat side airbag and curtain shield airbag to deploy simultaneously. Rear side collisions are detected by the side airbag sensor (for rear side) to deploy only the curtain shield airbag.

  3. REAR COLLISION

    1. The rear window curtain shield airbag is designed to help reduce shock to the rear outer passengers in the event of a rear collision.

    2. Rear collisions are detected by the center airbag sensor and two rear airbag sensors.

    3. Rear side collisions are detected by the rear airbag sensor to deploy only the rear window curtain shield airbag.


CONSTRUCTION AND OPERATION

  1. FRONT AIRBAG SENSOR

    1. The front airbag sensors are installed on the right and left radiator supports respectively.

    2. The front airbag sensor uses an electrical type deceleration sensor.

    3. The deceleration sensor is built into the front airbag sensor, and the distortion that is created in the sensor is converted into an electric signal based on the vehicle deceleration rate during a frontal collision. Accordingly, the extent of the initial collision can be detected in detail.

  2. SIDE AIRBAG SENSOR (FOR FRONT SIDE)

    1. The side airbag sensors are installed on the bottom of the right and left front doors respectively.

    2. The side airbag sensor uses an electrical type deceleration sensor.

    3. The deceleration sensor is built into the side airbag sensor, and the distortion that is created in the sensor is converted into an electric signal based on the vehicle deceleration rate during a front side collision. Accordingly, the extent of the initial collision can be detected in detail.

  3. SIDE AIRBAG SENSOR (FOR REAR SIDE)

    1. The side airbag sensors are installed on the bottom of the right and left rear pillars respectively.

    2. The side airbag sensor uses an electrical type deceleration sensor.

    3. The deceleration sensor is built into the side airbag sensor, and the distortion that is created in the sensor is converted into an electric signal based on the vehicle deceleration rate during a front side collision. Accordingly, the extent of the initial collision can be detected in detail.

  4. REAR AIRBAG SENSOR

    1. The rear airbag sensors are installed on the right and left quarter trim panels respectively.

    2. The rear airbag sensor uses an electrical type deceleration sensor.

    3. The deceleration sensor is built into the rear airbag sensor, and the distortion that is created in the sensor is converted into an electric signal based on the vehicle deceleration rate during a rear side collision. Accordingly, the extent of the initial collision can be detected in detail.

  5. CENTER AIRBAG SENSOR

    1. General

      1. The center airbag sensor is installed on the center floor under the instrument panel.
      2. The center airbag sensor consists of a deceleration sensor, safing sensor, ignition control circuit, and diagnostic circuit, etc.
      3. The center airbag sensor receives signals from the deceleration sensor and safing sensor built into the center airbag sensor and front airbag sensor, and determines whether the driver airbag, front passenger airbag, knee airbag, SRS seat cushion airbag and front seat belt pretensioner should be activated, and diagnoses system malfunctions.
      4. The center airbag sensor receives signals from the deceleration sensor and the safing sensor built into the center airbag sensor, the side airbag sensor (for front side) and the side airbag sensor (for rear side), and determines whether the front seat side airbag and the curtain shield airbag should be activated, and diagnoses system malfunctions.
      5. The center airbag sensor receives signals from the deceleration sensor and the safing sensor built into the center airbag sensor, the rear airbag sensor, and determines whether the rear window curtain shield airbag should be activated, and diagnoses system malfunctions.
      6. The center airbag sensor sends the airbag deployment signal to the ECM through CAN (Controller Area Network) communication to operate the fuel pump control.

    2. Deceleration sensor and ignition control circuit

      1. The deceleration sensor is built into the center airbag sensor, front airbag sensor, side airbag sensor (for front side), side airbag sensor (for rear side) and rear airbag sensor, and the distortion created based on the deceleration of the vehicle during a frontal, front side or rear side collision is converted into an electric signal.
      2. The ignition control circuit performs calculations based on the signal output from the deceleration sensors of the center airbag sensor, front airbag sensor, side airbag sensor (for front side), side airbag sensor (for rear side) and rear airbag sensor. If the calculated values are greater than the specified values, it activates an ignition operation.

    3. Safing sensor
      The safing sensor is built into the center airbag sensor. During a frontal, front side and rear side collision, the sensor turns on and outputs an ON signal to the center airbag sensor if a deceleration rate sent to the safing sensor is greater than the specified value.

    4. Back-up power source
      The back-up power source consists of a power supply capacitor and a DC-DC converter. When the power system does not function during a collision, the power supply capacitor discharges and supplies electric power to the system. The DC-DC converter operates as a boosting transformer when the battery voltage falls below a predetermined level.

    5. Diagnostic circuit
      This circuit constantly diagnoses system malfunctions. When a malfunction is detected, it turns on the SRS warning light on the combination meter assembly to inform the driver.

    6. Memory circuit
      When a malfunction is detected in the diagnostic circuit, it is coded and stored in the memory circuit.

  6. SRS WARNING LIGHT

    1. The SRS warning light is located on the combination meter assembly. It comes on to inform the driver of system trouble when a malfunction is detected in self-diagnosis of the center airbag sensor. Under normal operating conditions, when the ignition switch is turned to ON, it comes on for approximately 6 seconds and then goes off.


DEPLOYMENT CONDITION
If the vehicle collides and the shock is greater than the specified value, the SRS is activated automatically. The center airbag sensor assembly includes the safing sensor and deceleration sensor. The safing sensor is designed to turn on at a lower deceleration rate than the deceleration sensor.


  1. The center airbag sensor assembly determines whether ignition is necessary based on signals from the deceleration sensor and the front airbag sensor*1.
    If the safing sensor turns on simultaneously, current flows to the squibs to deploy the SRS as shown in the illustration below.


    C109526E28

    HINT:
    *1: In case of a front collision, the ignition signal could be output with the deceleration sensor ON signal even without a signal from the front airbag sensor.



  2. The center airbag sensor assembly determines whether ignition is necessary based on signals from the side airbag sensor (for front side). If the safing sensor turns on simultaneously, current flows to the squib to deploy the SRS as shown in the illustration below.


    C109527E30



  3. The center airbag sensor assembly determines whether ignition is necessary based on signals from the side airbag sensor (for rear side).
    If the safing sensor turns on simultaneously, current flows to the squib to deploy the SRS as shown in the illustration below*1.


    C109528E45

    HINT:
    *1: If the front seat side airbag assembly deploys, the curtain shield airbag assembly will also deploy, regardless of whether the signal is output from the side airbag sensor (for rear side).



  4. The center airbag sensor assembly determines whether ignition is necessary based on signals from the rear airbag sensor. If the safing sensor turns on simultaneously, current flows to the squib to deploy the SRS as shown in the illustration below.


    C195574E01