Airbag control unit with part number A2229009612

What does the airbag control unit A2229009612 do?

The airbag control unit A2229009612 coordinates the restraint system (SRS) of Mercedes-Benz. It evaluates signals from the crash sensors and in an accident decides within milliseconds on the triggering of airbags and seatbelt pretensioners. It also monitors the system and reports faults.

The unit checks the connected components constantly. If it detects a deviation, it switches on the airbag warning light in the instrument cluster.

After an accident the unit stores crash data and then locks itself.

Why does the control unit A2229009612 fail?

The most common cause is crash data stored in the control unit A2229009612 after an accident, even if no airbag was triggered. An ordinary diagnostic tool does not remove this data. Further causes are aged electronics, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

Airbag24 removes this data during the repair. The other causes lie in the electronics themselves.

Electronic components age, solder joints can go cold, and moisture or corrosion attack plug connectors. Voltage spikes, for example from a weak battery or a jump start, additionally stress the electronics.

How can you tell that the A2229009612 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently at the A2229009612 and thus indicates a defect. In an emergency, airbags and seatbelt pretensioners may then possibly not trigger.

An error message may also appear in the instrument cluster. In addition, a diagnostic tool that cannot connect to the control unit and a fault memory that cannot be cleared are present. Both findings point to a fault that needs checking.

Which vehicles is the A2229009612 fitted in?

The control unit A2229009612 is fitted in these vehicles: Mercedes-Benz S-Class W222 Saloon (2013-2020).

The list names the vehicles individually:

• Mercedes-Benz S-Class W222 Saloon (2013-2020)

Comparing the part number on the label of the removed unit with this page confirms that you have the correct unit. Whether the control unit is defective or a plug or cable causes the problem is shown only by the fault memory. Have it read out before removal.

For the same vehicles, we also repair control units with the part numbers A2229000303, A2229009908, A2229012601, A2229013503, A2229024709.

How does the repair of the A2229009612 work?

First read out the fault memory, enclose the log, disconnect the battery and then remove the control unit A2229009612. Next create a repair order online and send the unit in. Airbag24 usually needs 3–4 working days for inspection, repair and function test.

Airbag24 inspects the unit on the test bench, replaces defective components, deletes the crash data and carries out a function test. Afterwards your own unit goes back.

Our repairs come with 2 years' statutory liability for defects. The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.

How does the control unit A2229009612 get to Airbag24?

The unit goes to Airbag24 either as a parcel that you send yourself, or via a UPS collection booked for an extra charge. Airbag24 returns it by UPS after the repair.

The printed repair order belongs in the parcel; pack the control unit A2229009612 shock-proof.