Airbag control unit with part number 8H0 959 655 G

What does the airbag control unit 8H0 959 655 G do?

The airbag control unit 8H0 959 655 G is the central control unit of the restraint system (SRS) for Audi. It evaluates the crash sensors, determines in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. After a crash, it stores crash data and locks itself.

The unit is part of a chain of sensors, wiring and firing elements. If one of these links fails, the control unit reports the fault.

The message appears at the airbag warning light in the instrument cluster, so that the driver sees the fault.

Why does the control unit 8H0 959 655 G fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed. Also possible are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

A normal diagnostic tool cannot erase crash data. Even when the vehicle appears unremarkable, the stored data remain in the unit.

Moisture and corrosion attack plug connections, and cold solder joints can lose contact. Voltage spikes arise, for example, from a weak battery or from jump-starting that was not carried out properly.

How can you tell that the 8H0 959 655 G is defective?

The airbag warning light in the instrument cluster lights permanently or intermittently. Accompanying this, a fault message appears in the instrument cluster, the diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may fail to trigger because of such a fault.

The light is the direct indication of the defect. A brief going out does not mean the fault has been fixed.

Which vehicles is the 8H0 959 655 G fitted in?

The airbag control unit 8H0 959 655 G is fitted in these vehicles: Audi S4 B7 8H Convertible (2006-2009).

The overview of suitable vehicles:

• Audi S4 B7 8H Convertible (2006-2009)

Compare the part number on the label of the removed unit with this page to be sure it is the right unit. Also have the fault memory read out. Only the protocol shows whether the control unit is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 8H0 959 655 D, 8H0 959 655 F, 8H0959655E.

How does the repair of the 8H0 959 655 G work?

First have the fault memory read out and enclose the protocol. Then disconnect the battery, afterwards remove the control unit and create a repair order online. Send the well-packed unit in. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, renews defective components and erases the stored crash data. A function test follows, after which the unit goes back to you.

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 8H0 959 655 G get to Airbag24?

You send the unit as a parcel, or you book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

Print out the repair order and put it in the parcel. Pack the unit shock-proof.