Airbag units after an accident, replacing: Notes
NOTE:
- The control unit for the airbag can be used for up to three side/head airbag and/or belt tensioner deployments.
- The malfunction display "Control module defective" will appear after third deployment.
Airbag control module must be replaced:
- If driver/passenger airbag is deployed.
- After three side and/or head airbag deployments
- If housing is damaged
- In the event of tunnel deformation within 200 mm radius of control unit
Always replace the following:
- All triggered airbag units
Additionally, if front passengers airbag has been triggered:
- Instrument panel
- Supports for passengers airbag module which have been bent out of shape (must not be bent back into shape).
- Both front airbag sensors on front end
- Lateral acceleration sensor if floor pan around sensor has been deformed
Additionally, if drivers airbag has been triggered:
- Self-cancelling ring with slip ring.
- Both front airbag sensors on front end
- Lateral acceleration sensor if floor pan around sensor has been deformed
Additionally, if side airbag has been triggered:
- Lateral acceleration sensor on side where airbag has been triggered.
- With folding backrests: Side padding.
- Non-triggered lateral acceleration sensor if floor pan around sensor has been deformed.
Additionally, if head airbag has been triggered:
- Lateral acceleration sensor on side where airbag has been triggered.
- A, B, C and D-pillar trim
- Non-triggered lateral acceleration sensor if floor pan around sensor has been deformed
Additionally:
- All seat belts with triggered belt tensioners
A - Airbag control module triggered:
- Connect vehicle diagnostic, testing and information system VAS 5051 A and select vehicle system "15 - Airbag". For this purpose, the ignition must be switched on.
Front belt tensioner:
- Read measured value block, display group 001.
A triggered belt tensioner is indicated by the display "too great".
Rear belt tensioner (USA):
- Read measured value block, display group 002.
A triggered belt tensioner is indicated by the display "too great".
B - Airbag control module replaced:
- Connect vehicle diagnostic, testing and information system VAS 5051 A and select vehicle system "15 - Airbag". For this purpose, the ignition must be switched on.
- Interrogate DTC memory.
Fig 2: Identifying Content Of DTC Memory & Identification Of Fault On Diagnostic System VAS 5051 Display
A triggered belt tensioner is identified by the fault message "Belt tensioner igniter - Resistance value too great".
- In addition, the following must also be replaced, if necessary (visual check): all faulty components