Description of On Board Diagnostics

General information

Airbag 8 - BAE-Airbag-System (Basic triggering unit)


The airbag system comprises: Driver's airbag, passenger's airbag, two front side airbags, two front belt tensioners, two rear side airbags, two rear belt tensioners and three rear belt tensioners respectively, side curtain airbag, seat- occupied sensor passenger seat and rear bench seat as well as belt fastened query.

Additional On Board Diagnostic (OBD) features:
- 02 - Check DTC Memory: Further codes
- 08 - Read Measuring Value Block: Additional measuring value blocks 007, 008

In a crash situation the airbag control module sends a "Crash signal" to the central locking control module. This function is a passive safety feature. When the airbag and/or the belt tensioner is triggered it uses the central locking to release the door locks and blocks the interior switch. The "Crash-Signal" must be checked using Output Diagnostic Test Mode.

After the ignition is switched on, the airbag warning lamp -K75 comes on for about 4 seconds and then goes out again.

All airbag systems
Driver's airbag, passenger's airbag, front belt tensioners and, where applicable, rear side airbags and belt tensioners are triggered centrally by the control module for airbag -J234 in a crash situation when the preset triggering criteria are exceeded.

The control module detects malfunctions in the airbag system and stores them in a permanent memory.

If an airbag and/or belt tensioner is triggered, the control module will record the malfunction "Crash data stored".

In such cases the control module for the airbag (J234) must be replaced after
- The 1. triggering of driver's or passenger's airbag respectively.
- The 3. triggering of the front belt tensioners and/or side airbags.

After the 3. triggering it is not possible to erase the crash signal with the scan tool V.A.G 1551 up to 10.98 in vehicles with airbag 8.
- If the warning light -K75 does not go out after approx. 4 seconds this indicates a problem with the supply voltage for the airbag control module -J234. Check DTC Memory.
- If the warning lamp -K75 goes out and comes on again, this indicates either that the control module has not been encoded, that the wrong control module has been installed, or that a malfunction has occurred. Check DTC Memory.

When commissioning a new control module it must be encoded. Programming and Relearning


WARNING!
- 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.