Airbag control unit with part number 4F0959655H

What does the airbag control unit 4F0959655H do?

The airbag control unit 4F0959655H controls the restraint system (SRS) of Audi. It checks the crash sensors continuously and decides in an accident whether airbags and seatbelt pretensioners are triggered. An accident leaves crash data in the unit, after which it locks itself.

The manufacturer's number Bosch 0285010683 is also printed on the housing. The evaluation itself takes place within milliseconds as soon as an impact reaches the sensors.

In everyday life the function remains invisible until the unit reports a fault.

Why does the control unit 4F0959655H fail?

The most common cause is crash data that stays stored after an accident, even if no airbag triggered; an ordinary diagnostic tool does not remove it. In addition there are aged electronic components, cold solder joints, moisture, corrosion at plug connections and voltage spikes.

The unit creates crash data itself. Anyone who works only with a diagnostic tool can read it out but cannot remove it.

Aged components and solder joints lose reliability over time, and moisture attacks the contacts.

Voltage spikes occur, for example, when the battery is weak or when a vehicle is jump-started, and they add further strain to the electronics.

How can you tell that the 4F0959655H is defective?

You can recognise a fault from the airbag warning light, from fault messages in the instrument cluster, from the diagnostic tool having no connection, and from a fault memory that cannot be erased. In a crash there is then a possibility that airbags and seatbelt pretensioners do not trigger.

Signs at a glance:

• Airbag warning light in the instrument cluster is lit
• Fault message in the instrument cluster
• Diagnostic tool without connection to the control unit
• Fault memory cannot be erased

Have the finding checked promptly.

Which vehicles is the 4F0959655H fitted in?

The control unit 4F0959655H is fitted in these vehicles: Audi A6 C6 4F (2004-2008) and C6 4F Facelift (2008-2011).

The known vehicles for this number:

• Audi A6 C6 4F (2004-2008)
• Audi A6 C6 4F Facelift (2008-2011)

Check the part number on the label of the removed unit against this page; this only confirms that it is the correct unit. Have the fault memory read out before removal, because only this shows whether the control unit or a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 4F0 910 655 D, 4F0 910 655 Q, 4F0 959 655 B, 4F0 959 655 E, 4F0 959 655 G, 4F0910655B.

How does the repair of the 4F0959655H work?

First have the fault memory read out and attach the log to the unit. Then disconnect the battery and only afterwards remove the control unit, before you create the repair order online and send in the unit. Processing at Airbag24 usually takes 3–4 working days.

This sequence is safety-relevant for removal.

At Airbag24 the unit is examined on the test bench, defective components are repaired, crash data is erased and a function test is carried out. Your own unit is then returned 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 4F0959655H get to Airbag24?

You send the unit in as a parcel or book a UPS collection for an extra charge. After the repair it is returned to you by UPS.

Enclose the printed repair order and pack the unit so that it is shock-resistant.