Airbag control unit with part number 8UD 959 655 A

What does the airbag control unit 8UD 959 655 A do?

The airbag control unit 8UD 959 655 A is part of the restraint system (SRS) of Audi. It processes the signals from the impact sensors and decides in an accident, within a fraction of a second, on the triggering of airbags and seatbelt pretensioners.

In everyday use the unit works in the background and checks the system without pause. If it finds a fault, it records it and makes it visible via the airbag warning light.

If an accident has occurred, the control unit secures the crash data and goes into a lock. Repair is the only way to end it.

Why does the control unit 8UD 959 655 A fail?

The most common cause lies in the crash data that an accident leaves behind, even without a triggered airbag. Other causes are aged electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

This data remains in the memory. It cannot be removed with a standard diagnostic tool, which is why Airbag24 erases it during the repair.

Ageing also affects the components in the control electronics. Cold solder joints, moisture and corrosion at plug connectors can additionally lead to faults.

Voltage spikes are also among the causes, for example when a battery is weak or the vehicle is started with jump leads. They put a strain on the electronics.

How can you tell that the 8UD 959 655 A is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently. In addition, a fault message appears in the instrument cluster, the diagnostic tool does not find the control unit, and the fault memory cannot be cleared.

The warning light is the first visible sign. While it is lit, airbags and seatbelt pretensioners may not trigger in an emergency.

In such a case, have the system examined promptly rather than waiting.

Which vehicles is the 8UD 959 655 A fitted in?

The 8UD 959 655 A is found in these vehicles: Audi Q3 8U (2011-2014) and 8U Facelift (2014-2018).

Here is the assignment to this part number:

• Audi Q3 8U (2011-2014)
• Audi Q3 8U Facelift (2014-2018)

That the part number on the label matches this page only confirms that it is the right unit.

Have the fault memory read out before you remove the unit. Only this result shows whether the control unit is defective or whether a plug or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 8U0 959 655D, 8U0880201P BE7, 8U0959655, 8U0959655 P21827333, 8U0959655B.

How does the repair of the 8UD 959 655 A work?

First have the fault memory read out and enclose the log, then disconnect the battery and remove the control unit. Testing, repairing and function testing at Airbag24 usually take 3–4 working days.

Then create a repair order online and pack the unit well before sending it in.

Airbag24 examines the unit on the test bench, replaces defective components and erases the stored crash data. A function test completes the work, and then your own 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 8UD 959 655 A get to Airbag24?

You can reach Airbag24 with the unit either by sending a parcel yourself or by booking a UPS collection for an extra charge. The return is made by UPS.

Pack the control unit shock-proof and put the printed repair order in the parcel.