18:32. Safety cushions (SRS)

On cars the auxiliary security system (SRS – Supplemental Restrain System) better known as safety cushions is installed. The system consists of the sensors installed from the forward party of the car, safety cushions and the control unit and diagnostics. On the car the system of safety cushions of the HAE-3 type is installed. The HAE-3 system can be installed in various executions of DAB 2BPT, DAB PAB 2BPT, DAB PAB 2BPT 2FSAB (DAB – a safety cushion of the driver, PAB – a safety cushion of the forward passenger, BPT – a natyazhitel of a seat belt, FSAB – a side safety cushion).

SRS consists from: an air chamber from the driver located in the center of a steering wheel and containing the curtailed pillow and the block of a gas generator; the air chamber from the forward passenger located in the dashboard and containing the curtailed pillow and the block of a gas generator; the side air chambers located in backs of the driver and forward passenger and containing the curtailed pillows and the block of a gas generator.

The SRSCM control unit is located on a car floor under a radiator of a heater and controls system of safety cushions and includes: the accelerometer which defines delay of the car; the spiral wire (spring) located in a steering column; electric chains and sockets; the knee buffer located under a steering column. The spiral wire transmits a signal irrespective of the provision of a steering wheel.

The collision moment defines the SRSCM block on the basis of information from the accelerometer which constantly controls acceleration of the car.

Deployment of a safety cushion happens at front or almost head-on collision to moderate or big effort.

The pyrotechnic gas generator will transform the operating electric signal to an ignition signal therefore powder decays, inflating a safety cushion bag.

For service of safety cushions or the SRS components only specially trained personnel have to be allowed. At service of SRS it is necessary to show extreme care to avoid traumatizing personnel at unauthorized expansion of safety cushions of the driver or forward passenger.

Precautionary measures

At violation of the sequence of shutdown or service of system of safety cushions there can be unauthorized expansion of safety cushions and a drawing serious injuries. Also, unqualified service of system of safety cushions can lead to the fact that the safety cushion will not work at collision.

Before service performance, including removal or installation of elements of system, carefully implement the following recommendations.

  1. Before service of system of safety cushions be convinced that not less than 30 passed from later switching off of ignition and a detachment of a wire from the negative plug of the rechargeable battery. The system of safety cushions is equipped with an emergency power source which allows to develop safety cushions in case of a detachment of wires from the rechargeable battery at accident. Time during which the emergency power source provides with energy system of safety cushions makes 150 ms.
  2. At a wire detachment from the negative plug of the rechargeable battery memory of hours and sound systems is erased. Before work take information from sound systems. After completion of works determine time on hours and carry out repeated installation of sound systems.
  3. It is difficult to check signs of failure of system of airbags of safety so diagnostic codes become the most important source of information by search of malfunctions.
  4. By search of malfunctions of system of airbags of safety before a detachment of the rechargeable battery check the codes of malfunctions brought in memory.
  5. Do not use spare parts of safety cushions from other cars.
  6. Do not sort and do not repair elements of system of airbags of safety.
  7. If any SRS component fell or on it there are cracks, dents or other defects in the case, an arm or the socket, replace them with new.
  8. After work execute check of system of airbags of safety.
    In certain cases the electric chain of a control lamp of safety cushions can be broken by other malfunction of a chain. Therefore if the control lamp of safety cushions constantly burns, check that, all DTC codes are erased from memory.
  9. When carrying out electrowelding works surely disconnect a wire from the negative plug of the rechargeable battery.

Module (DAB, RAV, SAB)

DAB modules (safety cushion of the driver), RAV (a safety cushion of the forward passenger), DSAB (a side safety cushion of the driver) and PSAB (the side passenger airbag) consist of the device of a dehiscence and a pillow. The device of a dehiscence (gas generator) is located in a safety cushion. At head-on collision of sufficient force for short circuit of the SRSCM sensor through a contour of operation of a safety cushion current begins to proceed. This current sets fire to a charge of a gas generator and the safety cushion reveals.

  1. At removal of a safety cushion or work with its new safety cushion it is necessary to have so that the surface of a pillow was directed up. At the same time the lever of blocking of the socket with double blocking has to be in the blocked state.
  2. Never measure the safety cushion pyro resistance as it can lead to its operation.
  3. You store safety cushions at a temperature no more than 93 °C, lack of humidity and electric hindrances.
  4. When using electric welding before work disconnect sockets from a safety cushion.

Plait of wires of SRS

The plait of SRS is located in a tube of yellow color which differs from plaits of wires of other systems. In sockets from DAB, PAB, DSAB, PSAB and BPT are available crossing points which close electric chains at a detachment of sockets that prevents an undesirable dehiscence of a safety cushion.

Control lamp of SRSCM

The control lamp of SRS located in a combination of devices copes from the SRSCM block.

At some malfunctions of SRSCM cannot function and, thus, cannot operate work as a control lamp. In these cases the lamp is directly activated from the corresponding chain which works irrespective of SRSCM.

  1. In the absence of tension brought to SRSCM a lamp burns constantly.
  2. In the absence of internal working tension the lamp burns constantly.
  3. If SRSCM is not connected, the lamp joins through a crossing point in the socket of a plait of wires.

Spiral spring

The spiral spring consists of two twisted coils. It is established between a steering column and a steering wheel and allows a steering wheel to rotate, constantly keeping contact of an electric chain of a security system.

The steering wheel has to be correctly established on a steering column with the spiral spring established in neutral situation, otherwise the rupture of a wire or other malfunctions is possible.

Safety cushion of the driver and spiral wire

Removal

 PERFORMANCE ORDER

  1. Disconnect a wire from the negative plug of the rechargeable battery.

Before service of system of safety cushions be convinced that not less than 30 passed from later switching off of ignition and a detachment of a wire from the negative plug of the rechargeable battery.

  1. Uncover a steering wheel and a six-sided key verify bolts of fastening of a safety cushion of the driver.
  1. At a detachment of the electric socket of a spiral wire of a safety cushion install the lock device on the socket directed outside.

At a detachment of the electric socket of a spiral wire from a safety cushion do not make great efforts.

  1. Remove a safety cushion of the driver.

The removed safety cushion needs to be stored in the pure dry place, face up.

  1. Stripper 09561–11002 remove a steering wheel.
You do not knock on a steering wheel as it can damage the protective mechanism of a steering column and reduce degree of protection of the driver at head-on collision.

Check of a safety cushion

With any defects it is necessary to replace a safety cushion.

Do not try to measure resistance of an electric chain of a pyrotechnic gas generator of a safety cushion as perhaps unauthorized expansion of a safety cushion of the driver.


 PERFORMANCE ORDER

  1. Check a safety cushion cover for lack of dents, cracks or deformation.
  2. Check a safety cushion for lack of cave-in, splitting or deformation.
  3. Check a condition of hooks and sockets for absence of damage, oxidations of contacts of the socket and damages of a plait of wires.
  4. Check the case of a pyrotechnic gas generator of a safety cushion for lack of dents, cracks or deformation.
  5. Put a safety cushion to a steering wheel to check its combination and suitability.

Check of a spiral wire (spring)

 PERFORMANCE ORDER

  1. With any defects it is necessary to replace a spiral wire.
  2. Check electric sockets and a yellow protective pipe for absence of damage and oxidations of contacts of the socket.

Safety cushion of the forward passenger

Removal

  1. Do not sort and do not repair elements of system of a safety cushion.
  2. If the safety cushion fell or on it water, lubricants or oil got, and also if there are cracks, dents or other defects in the case or the socket, replace a safety cushion.
  3. The removed safety cushion needs to be stored in the pure dry place, face up. Have no on a safety cushion foreign objects which at expansion of a safety cushion can put serious injuries.
  4. Do not subject a safety cushion to influence of temperature above 93 °C.
  5. Not deployed block of a safety cushion has to settle down only according to the ordered procedures.
  6. Do not try to measure resistance of an electric chain of a pyrotechnic gas generator of a safety cushion as perhaps unauthorized expansion of a safety cushion of the driver.
  7. After operation of a safety cushion it needs to be replaced together with a wire which was affected by gases of a pyrotechnic gas generator.

 PERFORMANCE ORDER

  1. Disconnect a wire from the negative plug of the rechargeable battery.

Before service of system of safety cushions be convinced that not less than 30 passed from later switching off of ignition and a detachment of a wire from the negative plug of the rechargeable battery.

  1. Remove a ware box.
  2. Disconnect the electric socket of a safety cushion.
  3. Remove the dashboard and a safety cushion.
  4. The external layer of a safety cushion of the forward passenger is combined with the dashboard therefore at a dehiscence of a safety cushion it is necessary to replace the dashboard.