AIRBAG SYSTEM

Info Added 2017-04-18


  1. FUNCTION OF MAIN COMPONENTS


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

      Components Outline
      Airbag Sensor Assembly

      • In the event of a frontal collision, the airbag sensor assembly receives signals from either of the front airbag sensors. The airbag sensor assembly receives the signal via its judgment circuit and also receives another signal from the safing sensor built into the airbag sensor assembly. After receiving a signal from at least one of the front airbag sensors and the safing sensor, the airbag sensor assembly determines whether the driver airbag, front passenger airbag, driver knee airbag*1, curtain shield airbags*2, front seat belt pretensioners and rear seat belt pretensioners*3 should be deployed.

      • In the event of a side or rear side collision, the airbag sensor assembly receives signals from the door side airbag sensor, No. 1 side airbag sensor, floor side airbag sensor or No. 2 side airbag sensor. The airbag sensor assembly receives the signal via its judgment circuit and also receives another signal from the safing sensor built into the airbag sensor assembly. After receiving a signal from at least one of the side sensors and the safing sensor, the airbag sensor assembly determines whether the side airbags, curtain shield airbags, front seat belt pretensioners and rear seat belt pretensioners*3 should be deployed.*2

      • Sends an airbag deployment signal to the ECM and telematics transceiver*4.
      SRS Driver Airbag (Horn Button Assembly) Used as supplements to the seat belts to help reduce impact to the occupants.
      SRS Front Passenger Airbag (Instrument Panel Passenger Airbag without Door Assembly)
      SRS Driver Knee Airbag (Lower No. 1 Instrument Panel Airbag Assembly)*1
      SRS Side Airbag LH/RH (Front Seat Airbag Assembly LH/RH)*2
      SRS Curtain Shield Airbag LH/RH (Curtain Shield Airbag Assembly LH/RH)*2
      Front Airbag Sensor LH/RH Based on the deceleration of the vehicle during a frontal collision, distortion is created in the sensor and is converted into an electrical signal.
      Door Side Airbag Sensor LH/RH*2 Detects deformation of the front doors during a side collision using the pressure sensor and sends signals for the airbag sensor assembly to determine if deployment of SRS components is necessary.
      No. 1 Side Airbag Sensor LH/RH*2 Based on the deceleration of the vehicle during a side or rear side collision, distortion is created in the sensor and is converted into an electrical signal.
      Floor Side Airbag Sensor LH/RH*2
      No. 2 Side Airbag Sensor LH/RH*2
      Front Seat Outer Belt Assembly LH/RH Used to help reduce impact to the occupants.
      Rear Seat 3 Point Type Outer Belt Assembly LH/RH*3
      Seat Position Airbag Sensor*5 Detects the slide position of the driver seat.
      Airbag Cut Off Switch Cylinder Sub-assembly*6 The airbag cut off switch cylinder sub-assembly suspends the instrument panel passenger airbag without door assembly operation.

      Combination Meter Assembly


      • SRS Airbag Warning Light

      		 During airbag system malfunction, illuminates the SRS airbag warning light to warn the driver.

      Clock Assembly*6


      • AIRBAG ON/OFF Indicator Light

      		 Illuminates to inform the occupants whether the airbags for front passenger are active state or inactive state.
      ECM Stops the fuel pump when the airbag deployment signal is received.
      Telematics Transceiver*4 Receives an airbag deployment signal from the airbag sensor assembly, and automatically makes the emergency call of automatic emergency call service.
      Network Gateway ECU Relays and transmits each CAN communication data signal.

      *1: Models with SRS driver knee airbag

      *2: Models with SRS side airbag

      *3: Models with rear pretensioners

      *4: Models with manual (SOS) switch

      *5: Except models for Russia and General Countries

      *6: Models with airbag cut off switch cylinder

  2. SYSTEM CONTROL


    1. Airbag for Frontal Collision


      1. There are 2, 4*1 or 5*2 airbags which deploy in the event of a frontal collision: the horn button assembly, instrument panel passenger airbag without door assembly, lower No. 1 instrument panel airbag assembly*2 and curtain shield airbag assemblies*1. These airbags deploy simultaneously, although the curtain shield airbag assemblies may not deploy in some cases depending on the severity of the collision.*3 The horn button assembly use dual-stage control.*4 In addition, the front pretensioners contained in the front seat outer belt assemblies and rear pretensioners contained in the rear seat 3 point type outer belt assemblies*5 are also activated.


        • *1: Models with SRS side airbag

        • *2: Models with SRS driver knee airbag

        • *3: Models for Australia

        • *4: Models with airbag cut off switch cylinder for Europe or models for Australia

        • *5: Models with rear pretensioners

      2. The airbag sensor assembly detects the information indicated below from various sources in order to activate the dual-stage control.*


        • *: Models with airbag cut off switch cylinder for Europe or models for Australia

      3. For a frontal collision, if a front airbag sensor detects an impact, it informs the airbag sensor assembly. The airbag sensor assembly causes the horn button assembly, instrument panel passenger airbag without door assembly, lower No. 1 instrument panel airbag assembly*1 and curtain shield airbag assemblies*2 to deploy. Meanwhile, the airbag sensor assembly activates the front seat belt pretensioners and rear seat belt pretensioners*3.


        • *1: Models with SRS driver knee airbag

        • *2: Models with SRS side airbag

        • *3: Models with rear pretensioners

        B003XHSE01
        B003XHVE01

      4. Deceleration sensors used for the SRS airbag system are installed on various parts on the vehicle and calculate the deceleration (or acceleration) rate of each part during a collision.

      5. Depending on the situation, the airbag sensor assembly sends a deployment signal to each airbag based on the information from each sensor.

      6. Frontal collision signals are produced based on the information from the airbag sensor assembly and front airbag sensors. Frontal collision signals are used to deploy the airbags and activate the pretensioners as indicated in the table below.

        B003XHPE04

    2. Airbag for Side/Rear Side Collision (Models with SRS Side Airbag)


      1. There are 2 airbags which deploy in the event of a severe side collision: the front seat airbag assembly and curtain shield airbag assembly. These airbags deploy simultaneously. Additionally, at the same time, the front seat belt pretensioners and rear seat belt pretensioners* are also activated.


        • *: Models with rear pretensioners

      2. For a side collision, if the door side airbag sensor, No. 1 side airbag sensor or floor side airbag sensor detects an impact, it informs the airbag sensor assembly, and the airbag sensor assembly causes the front seat airbag assembly and curtain shield airbag assembly to deploy simultaneously, and activates the front seat belt pretensioners and rear seat belt pretensioners*.


        • *: Models with rear pretensioners

        B003XH8E01

      3. The front seat airbag assembly and curtain shield airbag assembly are deployed and the front pretensioner in the front seat outer belt assembly LH or RH and rear pretensioner in the rear seat 3 point type outer belt assembly LH or RH* are activated based on signals from the door side airbag sensors, No. 1 side airbag sensors, floor side airbag sensors and airbag sensor assembly.


        • *: Models with rear pretensioners

        B003XHQE01

      4. For a rear side collision, if the No. 2 side airbag sensor and floor side airbag sensor detects an impact, it informs the airbag sensor assembly and the airbag sensor assembly causes the curtain shield airbag assembly to deploy, and activates the rear seat belt pretensioners*.


        • *: Models with rear pretensioners

        B003XGME01

      5. The curtain shield airbag assembly is deployed and rear pretensioner in the rear seat 3 point type outer belt assembly LH or RH* is activated based on signals from the No. 2 side airbag sensors, floor side airbag sensors and airbag sensor assembly.


        • *: Models with rear pretensioners

        B003XFSE01

    3. Primary Check Illumination Control


      1. After the ignition switch is turned to ON, the airbag sensor assembly illuminates the SRS airbag warning light in the combination meter assembly for approximately 6 seconds and conducts the primary check. During the primary check, the ignition of airbags is prohibited and a diagnosis of the airbag sensor assembly is performed. If a malfunction is detected during the primary check, the SRS airbag warning light remains on even after the 6 seconds have elapsed.

      2. After the ignition switch is turned to ON, the airbag sensor assembly operates the passenger AIRBAG ON/OFF indicator lights as shown below to check for an open in the indicator light circuits.*


        • *: Models with airbag cut off switch cylinder

        B003XHJE54

  3. DIAGNOSIS


    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 airbag warning light.

    2. The airbag sensor assembly outputs malfunction data and Diagnostic Trouble Codes (DTCs) to the Global TechStream (GTS).

    3. The DTCs can be read after connecting the Global Techstream (GTS) to the DLC3. For details, refer to the Repair Manual.

    4. If the SRS airbags deploy, the airbag sensor assembly will turn on the SRS airbag warning light. However, unlike the ordinary diagnosis function, a DTC will not be stored. The SRS airbag warning light cannot be manually turned off. It is necessary to replace the airbag sensor assembly with a new one.