Airbag control unit with part number 3Q0959655S

What does the airbag control unit 3Q0959655S do?

The airbag control unit 3Q0959655S is the central control unit of the restraint system (SRS) for Skoda. It evaluates the signals from the crash sensors and decides in an emergency, within milliseconds, which airbags and seatbelt pretensioners are triggered.

The control unit also monitors the entire system continuously. If it detects a fault, it shows it via the airbag warning light in the instrument cluster.

After an accident the control unit stores crash data and locks itself. The lock is only lifted by the repair. Without this control unit, the restraint system lacks control, even if the airbags and seatbelt pretensioners themselves are intact.

Why does the control unit 3Q0959655S fail?

The most common cause is crash data stored after an accident, even if no airbag was triggered; a normal diagnostic tool cannot remove it. Other causes are aged electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

The other causes at a glance:

• aged electronic components
• cold solder joints
• moisture and corrosion at plug connectors
• voltage spikes, for example from a weak battery or jump-starting

The crash data is one of the causes that cannot be eliminated with an ordinary diagnostic tool. Which of the other causes applies in an individual case is only shown by the inspection of the removed unit.

How can you tell that the 3Q0959655S is defective?

A defect shows itself through the airbag warning light in the instrument cluster, which lights constantly or intermittently, through a fault message in the instrument cluster, through a missing connection to the diagnostic tool, and through a fault memory that cannot be cleared. In that case airbags and seatbelt pretensioners may possibly not deploy in an emergency.

• Airbag warning light in the instrument cluster lights constantly or intermittently
• Fault message in the instrument cluster
• The diagnostic tool gets no connection to the control unit
• The fault memory cannot be cleared

Even a light that only comes on at times is a warning you must not ignore. If the indicators report a fault, reading the fault memory helps with classification.

Which vehicles is the 3Q0959655S fitted in?

The control unit 3Q0959655S is fitted in these vehicles: Skoda Octavia 3 [5E] (2012-2017) and 3 [5E] Facelift (2017-2020).

The following overview shows the vehicles assigned to this part number.

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

Compare the part number on the label of the removed unit with this page, and you will know that it is the right unit. Whether the control unit is defective or a plug or cable is the cause is shown only by reading the fault memory, which you should therefore have done beforehand.

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 3Q0959655S work?

First have the fault memory read out and attach the log; then disconnect the battery and only then remove the control unit. Then create a repair order online and send in the well-packed unit. Airbag24 inspects it on the test bench, replaces defective components, erases stored crash data and carries out a function test; processing usually takes 3–4 working days.

The sequence serves your safety. The log records the condition of the system before removal, and you disconnect the battery before working on the control unit.

After the function test, your own repaired control unit is 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 3Q0959655S get to Airbag24?

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

Place the printed repair order in the parcel and pack the control unit shockproof before handing it over.