A3 Mk1
Self-diagnosis of airbag system BTU (Basic Triggering Unit) with and without side airbag
General notes
Vehicles ä 1998: The airbag system contains: Driver's airbag, passenger's airbag, and 2 front belt tensioners. In a crash situation, these are actuated centrally by the airbag control unit (J234) when certain specified triggering criteria are exceeded. Vehicles 1998 ä: The airbag system contains: Driver's airbag, passenger's airbag, two front seat belt tensioners, two side airbags at the front, and 2 rear belt tensioners. In a crash situation, these are actuated centrally by the airbag control unit (J234) when certain specified triggering criteria are exceeded. Self-diagnosis can be used to block or activate the passenger's airbag . Vehicles as of production date CW 27.99 The airbag system contains: Driver's airbag, passenger's airbag, two front seat belt tensioners, two side airbags at the front, and 2 rear belt tensioners. In a crash situation, these are actuated centrally by the airbag control unit (J234) when certain specified triggering criteria are exceeded. In addition to using the airbag key switch it is also possible to block or activate the passenger airbag via the function "adaption" => Page 01-55. If an airbag and/or belt tensioner is triggered, the control unit will record the fault "Crash data stored". In such cases the control unit for the airbag (J234) must be renewed after
After the 3rd triggering it is not possible to erase the crash signal with the fault reader V.A.G 1551 up to CW 27.99 in vehicles with airbag 8. All vehicles: Independent from the nature and intensity of the accident, the airbag control unit sends a "Crash Signal" to the control unit for the central locking system. This function is a passive safety feature. If an airbag is triggered it releases the door locks and tailgate lock via the central locking system, disables the internal switch and shuts off the fuel supply. The interior light is also switched on. The "Crash-Signal" must be checked using final control diagnosis => Page 01-34. The control unit detects faults in the airbag system and stores them in a permanent memory. After the ignition is switched on, the airbag warning lamp (K75) comes on for about 4 seconds and then goes out again. If it then flashes for a further 12 seconds this indicates that the passenger airbag is blocked.
Important:
Wiring must only be checked by visual inspection. Never use electrical tests to check or measure continuity in the igniter circuits. Always switch off ignition before inspecting wiring. |