Airbag control unit with part number 5QF959655AS

What does the airbag control unit 5QF959655AS do?

The airbag control unit 5QF959655AS coordinates the restraint system (SRS) of Seat. It evaluates the crash sensors and, in an emergency, decides which airbags and seatbelt pretensioners to trigger, within milliseconds.

Outside an accident, the unit continuously checks the function of the system. It stores any faults it finds and indicates them via the airbag warning light.

After an accident, the unit stores crash data and locks itself. The following section explains the causes of a failure.

Why does the control unit 5QF959655AS fail?

With the 5QF959655AS, the most common cause is crash data stored after an accident, even if no airbag has deployed. Other causes include ageing electronics, cold solder joints, moisture and corrosion on plug connections, and voltage spikes.

A normal diagnostic tool does not erase this data. The further causes include:

• ageing electronic components
• cold solder joints
• moisture and corrosion on plug connections
• voltage spikes, for example from a weak battery or from jump-starting

How can you tell that the 5QF959655AS is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, a fault message appears in the instrument cluster, the diagnostic tool cannot reach the control unit, and the fault memory cannot be cleared. In this state, airbags and seatbelt pretensioners may not deploy in an emergency.

The warning light is a hint from the vehicle itself, and it deserves attention.

Only the reading of the fault memory determines whether the control unit itself is defective. The light alone does not say that.

Which vehicles is the 5QF959655AS fitted in?

The control unit 5QF959655AS is fitted in these vehicles: Seat Ibiza 5 [6F] (2017-2021) and 5 [6F] Facelift (from 2021).

The vehicles are listed here:

• Seat Ibiza 5 [6F] (2017-2021)
• Seat Ibiza 5 [6F] Facelift (from 2021)

Two steps are important before removal. Compare the part number on the label of the unit with this page, so that you know it is the right unit. In addition, read out the fault memory first, as this is the only way to show whether the control unit itself is defective or whether a connector or cable is behind it.

For the same vehicles, we also repair control units with the part numbers 5QF 959 655 L, 5QF 959 655 N, 5QF959655AE, 5QF959655AG, 5QF959655AM, 5QF959655M.

How does the repair of the 5QF959655AS work?

In the repair of the 5QF959655AS, you read out the fault memory, attach the log and disconnect the battery; only then remove the control unit. At Airbag24, checking, repairing and testing take 3–4 working days as a rule.

Then create a repair order online and send the well-packed unit off. At Airbag24, it is checked on the test bench, defective components are repaired, stored crash data is erased, and a function test follows. The unit then comes 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 5QF959655AS get to Airbag24?

You can send the control unit 5QF959655AS as a parcel, or have it collected by UPS for an extra charge. Airbag24 returns it to you by UPS after the repair.

Pack the unit shockproof and include the printed repair order.