AIRBAG SYSTEM DETAILS

  1. FUNCTION OF MAIN COMPONENTS

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

      Component Function
      Center Airbag Sensor Assembly

      • The center airbag sensor assembly receives signals from the deceleration sensor and safing sensor built into the center airbag sensor assembly and one of the front airbag sensors, determines whether the driver airbag, front passenger airbag, driver knee airbag and front seat belt pretensioner should be activated, and diagnoses system malfunctions.

      • The center airbag sensor assembly receives signals from the deceleration sensor and the safing sensor built into the center airbag sensor assembly, the side airbag sensor assembly, rear airbag sensor*1, determines whether the front seat side airbag and the curtain shield airbag*1 should be activated, and diagnoses system malfunctions.

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

      • The center airbag sensor assembly sends the airbag deployment signal to the main body ECU through the CAN to operate the collision door lock release function.
      Driver Airbag Assembly These consist of an inflator, a bag, and so on. The inflator deploys gas in accordance with an expansion signal from the center airbag sensor assembly and deploys the bag.
      Front Passenger Airbag Assembly
      Driver Knee Airbag
      Front Seat Side Airbag Assembly
      Curtain Shield Airbag Assembly*1
      Front Airbag Sensor The front airbag sensor uses an electrical type deceleration sensor. Based on the deceleration of the vehicle during a front collision, a distortion is created in the sensor and converted into an electrical signal. Accordingly, the extent of the initial collision can be detected in detail.
      Side Airbag Sensor Assembly A deceleration sensor is enclosed in the side airbag sensor and rear airbag sensor*1. Based on the deceleration of the vehicle during a side or side rear collision*1, a distortion is created in the sensor and converted into an electrical signal.
      Rear Airbag Sensor*1
      Airbag Cut Off Switch Cylinder*2 The deployment of the front passenger airbag assembly at the time of collisions can be turned on and off as required.
      Passenger Airbag On Indicator Light*2 Illuminates when the airbag cut off switch cylinder is on.
      Passenger Airbag Off Indicator Light*2 Illuminates when the airbag cut off switch cylinder is off.
      SRS Warning Light The SRS warning light turns on to alert the driver when the center airbag sensor assembly detects a malfunction in the airbag system.

      • *1: Models with SRS curtain shield airbag

      • *2: 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 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. In case of a frontal collision, the center airbag sensor assembly determines whether airbag deployment or pretensioner activation 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.

        A0076CFE02

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

        • *: Models with SRS curtain shield airbag

        A0076QTE02

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

        • *: Models with SRS curtain shield airbag

      4. 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 rear airbag sensor.

        A0076UNE02

  3. FUNCTION

    1. Airbag Cut Off Switch Cylinder

      1. A cylinder to disable the deployment of the front passenger airbag assembly and the front passenger seat side airbag assembly has been provided as standard equipment on the models for Europe. This cylinder can be used if the deployment of those airbags is inconvenient, such as when the passenger is wearing a CRS seat belt.

      2. This cylinder 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 is on, the passenger airbag on indicator light will illuminate. Once the airbag cut off switch cylinder is turned to off, the front passenger 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 front passenger airbag has been disabled, the passenger airbag off indicator light in the center cluster illuminates to inform the occupant.

        A0076RGE01
        Text in Illustration
        *1 Passenger Airbag On Indicator Light *2 Passenger Airbag Off Indicator Light
        *3 Airbag Cut Off Switch Cylinder *4 Ignition Key*a
        *5 Mechanical Key*b - -

        • *a: Models without entry and start system

        • *b: Models with entry and start system

  4. CONSTRUCTION

    1. Driver Airbag Assembly

      1. The driver airbag assembly is built into the steering wheel pad.

      2. The driver airbag assembly consists of an inflator and a bag.

        A0076MFE01
        Text in Illustration
        *1 Inflator *2 Bag

    2. Front Passenger Airbag Assembly

      1. The front passenger airbag assembly is located in the upper section of the instrument panel of the front passenger seat.

      2. The front passenger airbag assembly consists of an inflator and a bag.

        A00769OE01
        Text in Illustration
        *1 Inflator *2 Bag

    3. Driver Knee Airbag Assembly

      1. The driver knee airbag assembly consists of an airbag door, an inflator, and a bag.

        A0076PHE01
        Text in Illustration
        *1 Airbag Door *2 Inflator
        *3 Bag - -

    4. Front Seat Side Airbag Assembly

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

        A0076U3E01

    5. Curtain Shield Airbag Assembly

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

        A0076IBE01

  5. SYSTEM CONTROL

    1. Airbag for Frontal Collision

      1. There are 3 types of airbags for frontal collisions: driver, front passenger, and knee airbags. These airbags deploy simultaneously.

        A0076M7E01

    2. Airbag for Side/Side Rear Collision

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

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

        • With the rear airbag for side collisions, if the rear airbag sensor detects an impact, it informs the center airbag sensor assembly via the side airbag sensor assembly, which causes the curtain shield airbag to be deployed.*

          • *: Models with SRS curtain shield airbag

        A0076HBE01
        A0076LEE01

  6. DIAGNOSIS

    1. Summary

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

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

        A0076HNE01

    2. SRS Airbag System DTCs

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

      2. If the SRS airbag deploys, the center 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 center airbag sensor assembly with a new one.