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General Description

GENERAL DESCRIPTION

WARNING: Extreme care must be used when servicing the SRS to avoid injury to the service personnel (by inadvertent deployment of the air bags) or the driver (by rendering the SRS inoperative).

The Supplemental Restraint System (SRS) and seat belt with pre-tensioner is designed to supplement the driver's and front passenger's seat belts to help reduce the risk or severity of injury to the driver and front passenger by activating and deploying both front air bags in certain frontal collisions.

The SRS front air bags form an advanced air bag system together with sensors at the vehicle and sensors attached to the front seats.

The SRS consist of four air bag modules, SRS air bag control unit (SRS-ECU), two front impact sensors, two side impact sensors, SRS warning light, passenger air bag OFF indicator light, passenger seat belt warning light, clock spring, seat belt pre-tensioner, seat belt switch, seat slide sensor, occupant classification sensor and occupant classification-ECU. Air bags are located in the center of the steering wheel and above the glove box. Each air bag is made up of a folded air bag and an inflator unit. Side-airbags located inside the front seatback assemblies. The SRS-ECU under the floor console monitors the system and has a safing G-sensor and an analog G-sensor.

The front impact sensor is assembled in the radiator support panel to monitor impact in case of front impact. The side impact sensors inside the center pillars monitor the shock incurred by the sides of the vehicle. The SRS warning light on the combination meter indicates the operational status of the SRS. The clock spring is installed in the steering column. The seat belt pre-tensioner is built into the driver's and passenger's front seat belt retractor. The seat slide sensor is installed at the seat adjuster section of the driver seat in order to detect the driver seat slide position. The occupant classification sensor is installed underneath a rail of the passenger seat to detect the load on the seat. The passenger air bag OFF indicator light is installed to the center air outlet panel and illuminates when the passenger seat air bag is inactive. The passenger seat belt warning light is installed to the center air outlet panel and illuminates when the passenger is not wearing the seat belt. The seat belt switch detects whether the seat belt is used.

Only authorized service personnel should do work on or around the SRS components. Those service personnel should read this manual carefully before starting any such work.

SYSTEM OPERATION (FRONT AIR BAGS AND SEAT BELT WITH PRE-TENSIONER)




In case of a frontal collision, if the SRS-ECU and the front air bag safing G-sensor simultaneously detect an impact that based on criteria (turn ON), the SRS-ECU sends an ignition signal to the air bag modules (squibs) and seat belt pre-tensioners (squibs) on the driver and passenger sides, thus inflating the air bags and operating the seat belt pre-tensioners.

DRIVER'S SIDE AIR BAG MODULE

CAUTION: Improper services cause the sudden operation of driver's air bag module or the system to be inoperative. Do not disassemble or tamper with the air bag module to prevent the serious injury.




The driver's air bag module incorporates a 4-spoke steering wheel. The driver's air bag module is an assembly part consisting of an air bag, module cover, inflator, and their fasteners. The air bag is made from nylon and inflates by gas from the inflator. As a driver is being pressed to the air bag, it deflates discharging gas from two vents at the rear of the air bag to reduce the shock from the impact.

The driver's air bag deploys by changing its inflation pressure in two steps.

The inflator has two squib connectors to deploy the air bag in two steps.

FRONT PASSENGER'S SIDE AIR BAG MODULE

CAUTION: Improper services cause the sudden operation of driver's air bag module or the system to be inoperative. Do not disassemble or tamper with the air bag module to prevent the serious injury.




The driver's air bag module incorporates a 4-spoke steering wheel. The driver's air bag module is an assembly part consisting of an air bag, module cover, inflator, and their fasteners.

The air bag is made from nylon and inflates by gas from the inflator. As a driver is being pressed to the air bag, it deflates discharging gas from two vents at the rear of the air bag to reduce the shock from the impact.

The driver's air bag deploys by changing its inflation pressure in two steps.
The inflator has two squib connectors to deploy the air bag in two steps.

The front passenger air bag does not deploy at the front passenger seat is not occupied and when the occupant classification sensor in the front passenger seat senses a weight on the seat of less than 30 kg (66 pounds).

SEAT SLIDE SENSOR

CAUTION: Improper services cause the system to be inoperative. Do not disassemble or tamper with the seat slide sensor to prevent the serious injury.




The seat slide sensor is attached to the seat rail and provides the air bag control unit with information on the seat position.

The air bag control unit controls deployment output of the driver's air bag in accordance with the information from the sensor.

OCCUPANT CLASSIFICATION SENSOR AND ECU

CAUTION: Improper services cause the system to be inoperative. Do not disassemble or tamper with the occupant classification sensor to prevent the serious injury.




The occupant classification sensors are attached to the seat rails and provide the air bag control unit with information on the weight applied to the front passenger seat.

The air bag control unit controls deployment output of the front passenger's air bag in accordance with the information from the sensor. The front passenger's air bag does not deploy in an impact when the weight applied to the seat is sensed as less than 30 kg (66 pounds).

PASSENGER'S SEAT BELT WARNING LIGHT




The light normally comes on when the ignition switch is turned to the "ON" position and goes off a few seconds later.

The light comes on when a person sits on the front passenger seat but does not fasten the seat belt.

PASSENGER'S AIR BAG OFF INDICATOR LIGHT




The indicator normally comes on when the ignition switch is turned to the "ON" position and goes off a few seconds later. In the following situations, the indicator will stay on to show that the front passenger air bag is not operational.
- The occupant classification sensors sense as less than 30 kg (66 pounds). on the front passenger seat.
- The front passenger's seat is not occupied.

When the weight applied to the front passenger seat is sensed as less than 30 kg (66 pounds) or greater, the indicator goes off to show that the passenger front air bag is operational.