AIRBAG SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The main components in the airbag system have the following functions:

      Component Function
      Airbag Sensor Assembly

      • The airbag sensor assembly receives signals from the deceleration sensor and safing sensor built into the airbag sensor assembly and the front airbag sensor, determines whether the horn button assembly (driver side squib), instrument panel passenger without door airbag assembly, No. 1 instrument panel lower airbag assembly*1 and front seat outer belt assembly (pretensioner squib) should be activated, and diagnoses system malfunctions.

      • The airbag sensor assembly receives signals from the safing sensor built into the airbag sensor assembly, the side airbag sensor assembly*2, and the No. 2 side airbag sensor assembly*3, determines whether the front seat airbag assembly*2 and the curtain shield airbag assembly*3 should be activated, and diagnoses system malfunctions.

      • The airbag sensor assembly sends the airbag deployment signal to the ECM through the Controller Area Network (CAN) to operate the fuel pump control.

      • The airbag sensor assembly sends the airbag deployment signal to the main body ECU to operate the collision door lock release function.
      Horn Button Assembly (Driver Side Squib) These consist of an inflator, a bag, and so on. The inflator deploys gas in accordance with an expansion signal from the airbag sensor assembly and deploys the bag.
      Instrument Panel Passenger without Door Airbag Assembly
      No. 1 Instrument Panel Lower Airbag Assembly*1
      Front Seat Airbag Assembly*2
      Curtain Shield Airbag Assembly*3
      Front Airbag Sensor The front airbag sensor uses an electrical type deceleration sensor. Based on the deceleration of the vehicle during a frontal collision, a distortion is created in the sensor and converted into an electrical signal.
      Side Airbag Sensor Assembly*2 A deceleration sensor is enclosed in the side airbag sensor assembly*2 and No. 2 side airbag sensor assembly*3. Based on the deceleration of the vehicle during a side collision*2 or rear side collision*3, a distortion is created in the sensor and converted into an electrical signal.
      No. 2 Side Airbag Sensor Assembly*3
      Airbag Cut Off Switch Cylinder Sub-assembly*4 The deployment of the instrument panel passenger without door airbag assembly at the time of collisions can be turned on and off as required.
      Passenger Airbag On Indicator Light*4 Illuminates when the airbag cut off switch cylinder sub-assembly is on.
      Passenger Airbag Off Indicator Light*4 Illuminates when the airbag cut off switch cylinder sub-assembly is off.

      Combination Meter Assembly

      - SRS Warning Light

      		 The SRS warning light turns on to alert the driver when the airbag sensor assembly detects a malfunction in the airbag system.

      • *1: Models with No. 1 instrument panel lower airbag assembly

      • *2: Models with front seat airbag assembly

      • *3: Models with curtain shield airbag assembly

      • *4: Models for Europe

  2. OPERATING CONDITION


    1. If the impact of a collision is greater than the specified value, the SRS is activated automatically. The 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. In case of a frontal collision, the airbag sensor assembly determines whether airbag deployment is necessary based on signals from the deceleration sensor and the front airbag sensor. If the safing sensor turns on simultaneously, current flows to the squibs to deploy the SRS components as shown in the illustration below. However, a deployment ignition signal may be output with the deceleration sensor on signal even without a signal from a front airbag sensor.

        A005G0FE02

      2. In case of a side collision, the airbag sensor assembly determines whether airbag deployment is necessary based on signals from the side airbag sensor assembly. If the safing sensor turns on simultaneously with the side airbag sensor assembly, current flows to the squibs to deploy the SRS as shown in the illustration below:*


        • *: Models with front seat airbag assembly

        A005G9RE04

      3. In case of a rear side collision, the airbag sensor assembly determines whether airbag deployment is necessary based on signals from the No. 2 side airbag sensor assembly. If the safing sensor turns on simultaneously with the No. 2 side airbag sensor assembly, current flows to the squib to deploy the SRS as shown in the illustration below:*


        • *: Models with curtain shield airbag assembly

        A005FPKE04

  3. FUNCTION


    1. Airbag Cut Off Switch Cylinder Sub-assembly (Models for Europe)


      1. A switch to disable the deployment of the instrument panel passenger without door airbag assembly and the front seat airbag assembly* has been provided. This switch can be used if the deployment of those airbags is inconvenient, such as when the passenger is wearing a Child Restraint System (CRS) seat belt.


        • *: For front passenger

      2. This switch is located on the side surface of the front passenger side of the instrument panel. It is switched on or off using a mechanical key*1, which is supplied with the ignition key*2. When the airbag cut off switch cylinder sub-assembly is on, the passenger airbag on indicator light will illuminate. Once the airbag cut off switch cylinder sub-assembly is turned to off, the instrument panel passenger without door airbag assembly will be disabled regardless of the collision conditions.


        • *1: Models with entry and start system

        • *2: Models without entry and start system

      3. If the deployment of the instrument panel passenger without door airbag assembly has been disabled, the passenger airbag off indicator light in the center cluster illuminates to inform the occupant.

        A005GCEE03
        Text in Illustration
        *A Models without Entry and Start System *B Models with Entry and Start System
        *1 Passenger Airbag Off Indicator Light *2 Passenger Airbag On Indicator Light
        *3 Airbag Cut Off Switch Cylinder Sub-assembly *4 Ignition Key
        *5 Mechanical Key - -

  4. CONSTRUCTION


    1. Horn Button Assembly (Driver Side Squib)


      1. The inflator and bag are built into the horn button assembly.

        A005FVHE05
        Text in Illustration
        *1 Bag *2 Inflator
        *a A - A Cross Section - -

    2. Instrument Panel Passenger without Door Airbag Assembly


      1. The instrument panel passenger without door airbag assembly is located in the upper section of the instrument panel of the front passenger seat.

      2. The instrument panel passenger without door airbag assembly consists of an inflator and a bag.

        A005FO1E02
        Text in Illustration
        *1 Inflator *2 Bag
        *a A - A Cross Section - -

    3. No. 1 Instrument Panel Lower Airbag Assembly


      1. The No. 1 instrument panel lower airbag assembly consists of an airbag door, an inflator, and a bag.

        A005G5EE02
        Text in Illustration
        *1 Inflator *2 Bag
        *3 Airbag Door - -
        *a A - A Cross Section - -

    4. Front Seat Airbag Assembly


      1. Front seat airbag assemblies are installed in the seat backs of the driver seat and the front passenger seat. Each front seat airbag assembly is a one-piece design, consisting of an inflator and a bag.

        A005FOIE02
        Text in Illustration
        *1 Inflator *2 Bag
        *a A - A Cross Section - -

    5. Curtain Shield Airbag Assembly


      1. Curtain shield airbag assemblies are installed in the area close to the sides of the headliner. Each curtain shield airbag assembly is a one-piece design, consisting of an inflator and a bag.

        A005GC7E02
        Text in Illustration
        *1 Inflator *2 Bag
        *a A - A Cross Section - -

  5. SYSTEM CONTROL


    1. Airbag for Frontal Collision


      1. There are 3 types of airbags for frontal collisions: horn button assembly (driver side squib), instrument panel passenger without door airbag assembly and No. 1 instrument panel lower airbag assembly*. These airbags deploy simultaneously.


        • *: Models with No. 1 instrument panel lower airbag assembly

        A005FTTE02

    2. Airbag for Side/ Rear Side Collision


      1. The airbag for side collisions contains 2 types of airbags: front seat airbag assemblies*1 and curtain shield airbag assemblies*2. These airbags deploy simultaneously. The airbag for rear side collisions contains only the curtain shield airbag assemblies*2.


        • With the airbag for side collisions, if the side airbag sensor assembly*1 detects an impact, it informs the airbag sensor assembly, which causes the front seat airbag assembly*1 and curtain shield airbag assembly*2 to be deployed simultaneously.

        • With the airbag for rear side collisions, if the No. 2 side airbag sensor assembly*2 detects an impact, it informs the airbag sensor assembly via the side airbag sensor assembly*1, which causes the curtain shield airbag assembly*2 to be deployed.


        • *1: Models with front seat airbag assembly

        • *2: Models with curtain shield airbag assembly

        A005FX1E04
        A005FV6E05

  6. DIAGNOSIS


    1. Summary


      1. If the airbag sensor assembly detects a malfunction in the SRS airbag system, the airbag sensor assembly stores the malfunction data in memory, in addition to illuminating the SRS warning light.


        • The airbag sensor assembly outputs the malfunction data as 5-digit Diagnostic Trouble Codes (DTCs) to the intelligent tester II or the SRS warning light.

        A005FMYE04
        *1 Airbag Sensor Assembly
        *2 Combination Meter Assembly
        *3 - SRS Warning Light

    2. SRS Airbag System DTCs


      1. The 5-digit DTCs can be read after connecting an intelligent tester II to the DLC3.

      2. If the SRS airbag deploys, the airbag sensor assembly will turn on the SRS warning light. However, in contrast to the ordinary diagnosis function, a DTC will not be stored. The SRS warning light cannot be turned off. It is necessary to replace the airbag sensor assembly with a new one.

        Note

        After replacing the air bag sensor assembly, initialization of the yaw rate sensor and G sensor are required. For the actual procedure, refer to the Repair Manual.