Airbag and Tensioner Units (In Car)

In the Federal Republic of Germany the accident prevention regulations stipulate that airbag and seat belt tensioner units must be made unusable before scrap disposal. These safety measures are necessary because the pyrotechnic devices could cause injury if activated improperly. For example: It is dangerous to use cutting torches on cars with live airbags. Smelting carries the same risk.

To avoid creating more work for the technician or repair facility it is recommended that scrap disposal of the pyrotechnic devices be entrusted to a scrap dealer, who should carry out the safety measures. On receipt of these items the dealer should sign a declaration undertaking to comply with the accident prevention regulations when he scraps the pyrotechnic items.

With agreements of this kind it is essential to ensure that the pyrotechnic devices cannot be removed from the rest of the scrap and passed on for repair or reuse. They must first be made unusable for reconditioning by triggering (detonating). In order to do this, it is necessary to use an ignition device developed by Daimler-Benz, which renders the pyrotechnic devices completely unusable.




Checking Whether The Vehicle Is Equipped With Seat Belt Tensioner or Airbag and Seat Belt Tensioner
- The seat belt tensioners can be identified by the RS Airbag symbol on the lock tongue.
- The driver's airbag unit can be identified on the steering wheel cushion by the SRS Airbag marking.
- The front passenger's airbag unit can be identified by the SRS Airbag marking.
- A further identification feature is the warning lamp in the instrument cluster with the marking SRS.
- If necessary, activate seat belt tensioners and airbag units which have been removed or supplied separately.



There is an observation window (20) on the housing of the seat belt tensioners through which a notch can be seen. If no notch can be seen, the seat belt tensioner has been activated and must be replaced.

If the cushion plate of the airbag unit has not been destroyed, the airbag unit must be ignited.

SRS Airbag Ignition Device -from Daimler-Benz:

1. Battery Capacity Light
2. Battery Pre-ignition Button
3. Ignition Button
4. Rotary Selector Switch
- Selector Switch Positions:
Position No. 1 - Driver's Airbag
Position No. 2 - Seat Belt Tensioner [Driver / Front Passenger]
Position No. 3 - Front Passenger-Side Airbag
5. Airbag Ignition Warning Light




Ignition Device
In order to ignite the seat belt tensioner units via the seat belt tensioner test connection (x11/7), or in the case of vehicles with an airbag via test coupling/plug connector (x11/13), a separate adapter cable must be made which is not included in the ignition device (Component No. 126 589 00 90 00).

The adapter cable must be attached to plug connector 6 of the ignition device.








Self-made adaptor cables

Using the Ignition Device on installed airbag and seat belt tensioner units
1. Check whether steering wheel and steering column are securely mounted and whether the airbag unit is firmly attached to the steering wheel (after ignition of an airbag unit the steering wheel is damaged and must also be replaced).
2. Turn ignition key to position 0, disconnect and cover negative terminal of battery.
3. For airbags with seat belt tensioners disconnect red 12-pin plug Connectors X11/7 and X11/13.




4. Make contact between self-made adapter cable and plug connector 6. Connect the plug connector of the adaptor cable to the 12-pin plug of the airbag cable harness.




5. From the prescribed safe distance of 10 meters(32 ft.) - which is the length of the ignition cable - press Button 2 and Button 3 simultaneously. After ignition the warning indicator (5) will light up.
6. For seat belt tensioners (without airbag) connect self-made adapter cable to the 4-pin test connection (X11/7) of the seat belt tensioner.
- Seat Belt Tensioner Rotary Switch (4) position 2.





Arrangement of the 12-pin test coupling/plug connector and/or of the 4-pin seat belt tensioner test coupling in the vehicle under the front passenger's foot rest.




Connection Diagram of Scrapping Cable
10 Self-made adaptor cable
X11/7 Seat belt tensioner test connection
X11/13 12-pin airbag test coupling connector