Mercedes M-Class W163

since 1997 of release

Repair and car operation

System of additional safety (SRS)

Into number of devices and the components forming system of additional safety (SRS) enter:

1. Two forward (face-to-face) safety cushions. The module of a driver's safety cushion is placed in a nave of a steering wheel. The safety cushion of the forward passenger is placed in a special cavity in the right part of the dashboard of the car. The locations of both pillows are marked with precautionary inscriptions of "SRS AIRBAG";
2. Four lateral safety cushions of lobbies and back seats. Modules of lateral safety cushions are built in at the corresponding doors of the car;
3. The head pillows (curtains) of safety placed along lateral edges of the ceiling panel and providing additional protection of the heads of the driver and all passengers at lateral blows and a perevorachivaniye of the car;
4. The sensors of the directed overloads working at strong front/lateral blow;
5. Electronic system of self-diagnostics which at the included ignition provides continuous testing of sensors of overloads, the control unit, gas generators of pillows and connecting electroconducting of the corresponding chains;
6. The automatic emergency natyazhitel of the seat belts who have been built in in returnable devices of seat belts of forward seats;
7. Control lamp of refusals SRS which has been built in in the dashboard;
8. The spare independent power supply intended for duplication of the main power supply system in case of its exit out of operation during collision.

In an instrument guard of the car the special control lamp of SRS (is built in see. The section the Combination of devices, measuring instruments and control lamps and light indicators), intended for the prevention of the driver about revealed by self-diagnostics system refusals in system of additional safety. Depending on a car complete set operation of a control lamp testifies to possible malfunctions of modules of face-to-face/lateral safety cushions or devices of an automatic emergency tension of seat belts.

Principle of functioning of face-to-face safety cushions

Modules of face-to-face safety cushions are built in in a stupichny part of a steering wheel and in the panel the right part of the dashboard, is direct over the main ware box.

Sensors of the directed overloads react to excess of some limiting value which can arise at a 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 from shift the lower part of a trunk sitting. Forward safety cushions help to prevent a travmirovaniye of the driver and the forward passenger as a result of blow their head and a thorax about steering the 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 only is not excluded by one of pillows. Such becomes possible when the size of the directed overloads which have arisen at collision was on the verge of a range of sensitivity of sensors. In this case seat belts provide rather reliable protection of the driver and the forward passenger while the effect from operation of a safety cushion will be minimum.

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

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

After a road accident at which there was an operation of safety cushions, the volume of salon of the car looks slightly filled with smoke. Actually it is a suspension of a tonkodispersny powder by which covers of pillows in the combined condition are usually poured. People with a disease of respiratory organs can feel a certain discomfort from the gaseous products containing in air allocated by gas generators of pillows.

Principle of functioning of lateral and head safety cushions

Modules of lateral safety cushions are built in in the panel of lateral doors of the car. The locations of both lateral pillows are usually marked with "SIDE AIRBAG" inscriptions.

Gas generators of head pillows are located on lateral edges of the ceiling panel.

At strong lateral blow sensors of the directed overloads fix excess by arising loadings of some threshold value and give out information signal on the control unit which develops command for operations of a gas generator of the corresponding lateral safety cushion. Thus, if the blow has from the passenger seat, the corresponding lateral pillow will work even at absence on a seat of the passenger.

For ensuring the greatest efficiency of protection which is provided by safety cushions, the driver and the passenger sitting on a forward seat, should sit directly and to be fastened by seat belts.

Order of functioning of a control lamp of refusals of SRS

At ignition inclusion (the ignition key will turn in situation 2) the control lamp lights up for short time, then at once dies away that confirms about serviceability of functioning of all knots of system.

At any operation of a control lamp during any other moment the owner of the car should address at the first possibility for the help to specialists of car repair shop of the Mercedes-Benz company. The following belongs to number of such situations:

1. The control lamp does not join at ignition key turn in situation 2;
2. The control lamp continues to burn after implementation of start of the engine;
3. The control lamp is activated and burns in a constant or flashing mode during car movement.

In the presence of listed above malfunction signs the additional system of safety can refuse at car failure.

Seat belts with automatic emergency natyazhitel

Emergency automatic natyazhitel equipped returnable devices of three-anchor seat belts of forward seats and lateral places of a back seat of the second row. By Natyazhiteli are put in action at the strong face-to-face overloads arising at a head-on collision, and provide instant sample of a weak point of belts therefore tapes of the last densely cover a body sitting, in considerably degree raising extent of protection of the driver and the forward passenger.

Natyazhitel (And) is built in in assembly of the returnable mechanism of a belt. The order of using such seat belts is similar to an order of using the usual belts equipped with inertial returnable devices. The mechanism of operation of a natyazhitel is absolutely transparent for the user and does not demand from the last any additional skills and knowledge.

Activation of natyazhitel occurs only at considerable face-to-face overloads. Operation of modules is accompanied by loud cotton and a small dymoobrazovaniye.

It is necessary to notice that refusals of operation of natyazhitel at a head-on collision in most cases speak not malfunction of system, and that overloads arising at blow do not reach threshold value at which activation of modules is made.

As well as in case of safety cushions, modules of emergency natyazhitel are calculated on single operation and after that are subject to replacement assembled with belts, - address on firm car repair shops of the Mercedes-Benz company. All claims concerning refusals of the SRS components in the same place are accepted.

Maintenance of the elements SRS

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 should mean the next moments:

1. After operation of safety cushions they are subject to obligatory replacement together with the system control unit. Do not try to dismantle fulfilled pillows independently. These operations should be carried out only in the conditions of a car-care center workshop;
2. If operation of a control lamp of SRS indicates refusal existence in system, it is necessary to address immediately on the closest car repair shop of the Mercedes-Benz company where complete diagnostics and necessary regenerative repair of system will be made. Otherwise safety cushions can not work at a road accident and not execute the protective function;
3. Specially trained personnel is allowed to works with knots of additional system of safety only. It is forbidden to dismantle independently from the car of a safety cushion and emergency natyazhitel of seat belts. In default SRS or after emergency operation of safety cushions and natyazhitel of seat belts is necessary to address on Mercedes-Benz company car repair shop for carrying out repair or replacement of knots of system;
4. Do not open modules and do not change electroconducting of systems of safety cushions and devices of an automatic emergency tension of seat belts, - such intervention can lead to involuntary operation of pillows and natyazhitel and be at the bottom of a travmirovaniye of the performer or the people who were nearby;
5. Do not make replacement of forward seats without receiving preliminary consultation at Mercedes-Benz company car repair shop. Inaccurate or incorrect performance of replacement or removal of covers can lead to refusal of operation of lateral safety cushions in case of a road accident.

By car transfer to other person it is necessary to inform without fail the last on all established elements SRS with the indication of the corresponding points of the instruction on rules of use of the car.

On all equipped SRS models in places of placement of active elements of system special warning plates are established.