Audi 100 airbag control unit repair⁽¹⁾

What should be considered with Audi 100 airbag control units?

The airbag control unit in the Audi 100 evaluates the crash sensors, triggers the airbags and belt tensioners, and monitors the entire system. If it detects a fault, the airbag warning light in the instrument panel comes on.

After an accident, the control unit stores crash data and locks itself. A defective control unit can disable the entire airbag system. The airbag system is safety-relevant, so testing and removal should only be carried out by a specialist workshop.

Airbag24 repairs your own control unit, which you send to us for repair. Whether a particular fault can be repaired only becomes clear after testing in our workshop.

Which Audi 100 generations are there?

For the Audi 100, Airbag24 lists the 4A series, built from 1990 to 1994. This series is also referred to as the C4.

• 4A (1990–1994) – Audi 100 series, also referred to as C4

To check whether a vehicle belongs to this series, use its year of manufacture and vehicle identification number (VIN).

How do I identify my Audi 100 airbag control unit?

The part number on the label of the control unit determines the exact version. The vehicle's year of manufacture and equipment should also be checked before a repair is ordered.

The following part number is listed for the 4A series. The list does not claim to be complete; the number on your own unit always takes priority:

• 4A0959655

The fault memory may show codes such as 00588 (igniter, driver airbag, resistance fault), 00589 (firing circuit, passenger airbag, resistance too high) and 65535 (control unit defective). A single code, however, does not prove a defect. It is an indication that the workshop has to check.

Which airbag equipment does the Audi 100 have?

According to the sources reviewed, the driver airbag was standard equipment on the Audi 100. Whether a passenger airbag and side airbags are fitted depends on market, year of manufacture and trim level.

The information on the passenger side is contradictory. Some specifications list the passenger airbag as standard, others as an option or not at all. The fault codes for this series also relate to igniters for the front side airbags on the driver and passenger sides. You can check whether your vehicle has this equipment on the vehicle registration document or in the equipment documents.

The repair process runs as follows: have the fault memory read out. A specialist workshop first disconnects the battery and removes the control unit. You then create a repair order online and send the unit to Airbag24. Processing usually takes 3–4 working days (checking, repairing, testing).

The repaired control unit comes back with all vehicle data and is ready for use immediately after reinstallation — no coding or programming is required.