30.0 The belt tensioner is installed on the front seats:
1 - seat belt height adjuster
2 - belt tensioner with demolition charge
3 - waist belt
4 - automatic winder of the seat belt tape
5 - belt guide
The pretensioner is activated in a frontal collision, keeping the seat belt snug against the body and preventing the occupant from slipping under the belt. The tensioner only activates in the event of a severe frontal collision. Operation is provided by the control unit for the airbags and the belt tensioner. Depending on the severity of the impact, only the belt tensioner or the airbag is activated at the same time.
The control unit ignites a small explosive charge upon impact. The gases formed during the explosion of the charge push the piston in the tensioner tube forward. The piston is connected by a cable to the seat belt buckle. The buckle pulls down to remove any slack in the seatbelt at the shoulder and at the passenger's waist.
A deployed belt tensioner can be recognized by the warning light for the airbags and belt tensioner. Once the pretensioner has been deployed, the seat belt functions like a belt without a pretensioner.
The belt tensioner is maintenance free. After operation, it must be completely replaced.
Attention! When disposing of a broken belt tensioner, it must first be made to work. These works are carried out in the workshop.
To avoid triggering the belt tensioner inadvertently, the following safety precautions should be observed:
- The belt tensioner and the airbag system must only be replaced or repaired by a specialist workshop. Do not modify the design of these systems.
- When the tensioners are triggered, they must be completely replaced with new ones. Work must be done in a workshop. Changing the design of the tensioner is not allowed. If, as a result of an accident, the tensioners have worked, then they must be replaced with new ones together with the control unit. These works are also carried out in the workshop.
- Before starting work on the seat belt tensioners, disconnect the wire terminal «masses» (-) from the battery and insulate the negative terminal of the battery to avoid accidental contact. After that, you should wait about 5 minutes for the capacitor in the control unit to discharge.
- The removed serviceable belt tensioner should be stored in a safe place when performing major repairs to the car.
- Tensioner and control unit are shock sensitive. If the weight or control unit has fallen from a height of more than 50 cm, then their installation is not allowed.
- When performing welding work, the polar terminal of the welding machine should be mounted directly on the workpiece to be welded. It is recommended to disconnect the battery when performing welding work. When working on the bottom, during which the bottom vibrates as a result of hammer blows, the battery must be disconnected. After that, you should wait about 5 minutes for the capacitor in the control unit to discharge.
- The airbag and belt tensioner control unit is located on the center console in front of the gear lever. Do not put magnetic or magnetizing items there. This may cause malfunctions.
- The control unit and seat belt pretensioner must not be exposed to temperatures above 90°C, even for short periods. Damaged or defective tensioner parts cannot be repaired. Pretensioner and airbag components must not be forcibly opened.
- Independent dismantling and disposal of the tensioner is not allowed. Explosion hazard!
System Function Check
The warning light for the airbag system and the automatic seat belt tensioner should come on when the ignition is switched on and go out after about 3 seconds. after turning on the ignition.
The system is faulty if the control lamp does not light up when the ignition is switched on.
If the light does not light up or lights up at the moment of movement, then this is it. also indicates a malfunction in the system. In such cases, it should be assumed that the system of the airbag and the automatic belt tensioner is out of order and inoperable.