Airbag control unit with part number 3Q0959655AR

What does the airbag control unit 3Q0959655AR do?

The airbag control unit 3Q0959655AR is the control unit of the restraint system (SRS) for Seat and Skoda. It processes the signals from the crash sensors, decides in an accident within milliseconds whether airbags and seatbelt pretensioners are triggered, and monitors the entire system. If it detects a fault, it shows this via the airbag warning light.

Monitoring takes place during operation and not only when needed. This allows faults to be detected early, before they impair the function.

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

Why does the control unit 3Q0959655AR fail?

The most common cause is crash data stored in the unit after an accident, even if no airbag was triggered. A normal diagnostic tool cannot erase it. In addition, aged electronic components, cold solder joints, moisture and corrosion at plug connections, as well as voltage spikes, for example from a weak battery or a jump start, may be involved.

The crash data is at the top of the list because it remains in the memory even when the vehicle is long back on the road. The other causes concern the electronics and their surroundings.

Ageing and moisture act slowly, whereas voltage spikes act suddenly. Which cause applies in an individual case only becomes clear through examination of the unit.

How can you tell that the 3Q0959655AR is defective?

The airbag warning light in the instrument cluster lights up permanently or only intermittently. A fault message in the instrument cluster may also appear, and the diagnostic tool finds no connection to the control unit. If the fault memory also cannot be cleared, that is a clear sign.

As long as a fault is present in the system, airbags and seatbelt pretensioners may not trigger in an emergency. So do not ignore the warning light, but have the system checked promptly.

A missing connection to the diagnostic tool does not have to lie with the control unit alone. Cables and plug connections can be responsible too.

Which vehicles is the 3Q0959655AR fitted in?

The control unit 3Q0959655AR is fitted in these vehicles: Seat Leon 3 [5F] (2012-2020); Skoda Octavia 3 [5E] (2012-2017) and 3 [5E] Facelift (2017-2020).

The list shows the vehicles recorded for this part number.

• Seat Leon 3 [5F] (2012-2020)
• Skoda Octavia 3 [5E] (2012-2017)
• Skoda Octavia 3 [5E] Facelift (2017-2020)

The first step is to compare the part number on the label of the removed unit with this page. This only ensures that you have the right unit. The second step is to have the fault memory read before removal, because only this 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 3Q0 959 655 AA, 3Q0 959 655 AC, 3Q0 959 655 AS, 3Q0 959 655 BH, 3Q0 959 655 CM, 3Q0 959 655 CN.

How does the repair of the 3Q0959655AR work?

First, have the fault memory read out and attach the log. Then disconnect the battery, and only after that remove the control unit. Then create a repair order online and send the unit in well packed.

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. The unit then goes back to you. Processing at Airbag24 usually takes 3–4 working days; during this time, the unit is only checked, repaired and tested.

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 3Q0959655AR get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 sends the control unit back to you by UPS.

The printed repair order belongs in the parcel, and the unit should be packed shockproof.