2.2.2. System of additional safety (SRS)

Remember that pillows should not be considered as adequate replacement of seat belts at all. The driver and the forward passenger during the movement have to be fastened without fail by the belts adjusted as appropriate (see Elements of passive safety)!


The scheme of an arrangement of the SRS elements in interior of the car


Scheme of an arrangement of precautionary labels of SRS

Forward frontal and side safety cushions and also emergency natyazhitel of seat belts belong to the SRS elements. Safety cushions provide additional protection of the driver and forward passenger at strong directed front (frontal pillows) or onboard (side pillows) the overloads arising at emergency collisions of the car.

Emergency natyazhitel provide instant selection of a weak point of seat belts of front seats at the directed frontal overloads.

The scheme of an arrangement of the SRS elements — see the illustration Scheme of an Arrangement of the SRS Elements in interior of the car.

Modules of all SRS elements (safety cushions and emergency natyazhitel) are not subject to reuse and after operation have to be replaced without fail.

At inclusion of ignition there is a short-term operation of a control lamp of SRS (AIR BAG) on an instrument guard of the car. During activation of a lamp the module of self-diagnostics carries out a survey of a condition of components of system. If no violations during the diagnostic poll come to light, the control lamp has to go out about 7 seconds later.


Precautionary measures

On all equipped with safety cushions cars the special labels warning the driver and passengers about need of observance of the appropriate measures of precaution are established (see the illustration Scheme of an Arrangement of Precautionary Labels of SRS).


Frontal safety cushions

Modules of frontal safety cushions are built in in a stupichny part of a steering wheel (a driver's pillow) and the right top section of the dashboard, over a ware box (a passenger pillow) (see the illustration Scheme of an Arrangement of the SRS Elements in interior of the car). Activation of gas generators of frontal safety cushions happens at excess by appropriately directed overloads of some threshold value. It must be kept in mind that activation of pillows can happen not only at head-on collision of the car, as well as not at each front blow. The damage rate of the vehicle is not criterion of need of operation or failure of pillows.

Sensors of the directed overloads react to excess of some extreme value which can arise at strong head-on collision. On a signal of sensors the control unit includes gas generators of safety cushions, causing their instant filling.

During collision the seat belt holds the lower part of the trunk sitting from shift. Frontal safety cushions help to prevent traumatizing the driver and forward passenger as a result of blow by their head and a thorax about a steering wheel / dashboard.

As signals on operation of both safety cushions arrive from the same sensors, both pillows work at the same time. However, the probability of initiation of only one of pillows is not excluded. It becomes possible when the size of the directed overloads which arose at collision was on the verge of the range of operation of gas generators. In this case seat belts provide rather reliable protection of the driver and forward passenger while the effect of operation of a safety cushion is minimum.

Right after operation and performance by pillows of the functions gas from them is produced that allows the driver to keep the review and to manipulate freely all governing bodies of the car.

The full duration of process takes with sensors of overloads before production of gas from pillows fractions of a second the moment of giving of a signal. Operation of pillows happens so quickly that the human ear simply is not capable to apprehend cotton of gas generators when filling pillows.

After the road accident at which there was an operation of safety cushions the volume of interior of the car looks slightly smoke-filled. Actually it is a suspension of fine powder which usually pours covers of pillows in the put state. People with a disease of respiratory organs can feel a certain discomfort from the gaseous products which are contained in air allocated by gas generators of pillows.


Precautionary measures


Side safety cushions

Modules of side safety cushions are located in the special pockets equipped in external sidewalls of front seats are covered outside with decorative covers and provide protection of a humeral belt and the head of the driver and forward passenger at side blows and capsizing of the vehicle.

Activation of side safety cushions happens at excess by appropriately directed overloads of some threshold value. It must be kept in mind that activation of pillows can happen not only at side blows, as well as not at each similar blow. The damage rate of the vehicle is not criterion of need of operation or failure of pillows.

Operation of safety cushions is followed by quite loud cotton and small smoke emission which is not containing toxic components and not being an ignition sign. Nevertheless, inhalation of the smoke emitted by a gas generator can lead to insignificant irritation of mucous membranes and cause a short fit of coughing.

Right after operation gas from pillows is automatically pitted.

All preventions given above for frontal pillows adjusted for location of components work for side safety cushions.


Automatic emergency natyazhitel of seat belts of front seats

The scheme of an arrangement of modules of emergency natyazhitel — see the illustration Scheme of an Arrangement of the SRS Elements in interior of the car.

On some models for the purpose of ensuring additional protection of the driver / passenger forward seat belts are supplied with devices which at operation provide the automatic choice of a weak point of belts that helps to exclude a possibility of dangerous movements of the driver and passenger in case of the road accident.

Activation of pyrotechnic modules of emergency natyazhitel happens at the directed overloads arising during strong head-on collision and is followed by sharp cotton and insignificant smoking. Emission of forward safety cushions is at the same time made.

At operation of the device the seat belt remains in the tense situation until the bracket of its buckle is not taken out from the lock of the last.

Inclusion on an instrument guard of a control lamp of seat belts warns the driver about possible malfunctions in devices of automatic emergency natyazhitel of belts — the car should be driven away on car repair shop for conducting full check of SRS and performance of the corresponding recovery repair.

All preventions given above for frontal pillows adjusted for location of components work for emergency natyazhitel.


Control lamp of SRS

Negligence to signals of a control lamp of SRS can lead to the most serious consequences at refusal of safety cushions during the road accident!


The control lamp of AIR BAG which is built in in the speedometer dial is included in a chain of an electrical wiring of SRS and allows the driver to control any violations of a condition of all elements of system, including satellite sensors, the block of the diagnostic sensor, modules of safety cushions and all connecting electrical wiring (see the illustration Scheme of an Arrangement of the SRS Elements in interior of the car). Serviceability of a condition of emergency natyazhitel is controlled by a control lamp of seat belts (see above).


At the burning control lamp operation of safety cushions in an emergency is blocked!


Service and replacement

As it was already mentioned above, modules of all SRS elements (safety cushions and emergency natyazhitel) are among the disposable equipment, to recovery repair not subject and after operation have to be replaced without fail — as a reminder on need of replacement of modules of safety cushions on an instrument guard it will be necessary to burn a control lamp of AIR BAG. Replacement of SRS modules has to be made in the conditions of car repair shop. About ways of utilization the failed SRS components it is possible to cope with specialists of car service.

Safety cushions and devices of an automatic emergency tension of seat belts, practically do not need regular checks and maintenance. However the owner of the vehicle equipped as appropriate has to remember the following: