Airbag control unit with part number 3WA 959 655 AB

What does the airbag control unit 3WA 959 655 AB do?

The airbag control unit 3WA 959 655 AB is the central control unit of the restraint system (SRS) in Cupra. It processes the crash sensor signals, decides within milliseconds in an accident whether airbags and seatbelt pretensioners are triggered and monitors the system continuously.

If it detects a fault, the unit reports it via the airbag warning light in the instrument cluster. The fault is also stored in the fault memory.

After an accident, the control unit stores crash data and locks itself. The lock is lifted only by the repair.

Why does the control unit 3WA 959 655 AB fail?

Crash data stored after an accident are the most common cause, even if no airbag was triggered. A standard diagnostic tool cannot erase them.

Aged electronic components, cold solder joints, and moisture and corrosion at plug connections are also possible causes. Voltage spikes, for example from a weak battery or a jump-start, can also disturb the unit.

Which of the other causes is present only becomes clear during the check.

How can you tell that the 3WA 959 655 AB 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 finds no connection to the control unit, and the fault memory cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may not deploy in such a case. The warning light shows the finding directly, so a prompt check is worthwhile.

Which vehicles is the 3WA 959 655 AB fitted in?

The airbag control unit 3WA 959 655 AB is fitted in these vehicles: Cupra Born 10E (from 2021).

The following overview shows the models assigned to this page.

• Cupra Born 10E (from 2021)

Compare the part number on the label of the removed unit with this page. This only confirms that it is the correct unit. Also have the fault memory read out beforehand, because only this log 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 1EA 959 655 DT.

How does the repair of the 3WA 959 655 AB work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only after that remove the control unit. Next, create a repair order online and send in the well-packed unit. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components and carries out a function test. The unit then goes back to you. With this control unit, erasing the crash data is often not possible. If the crash data needs to be erased, please contact us briefly before sending the unit in – we will check your part number.

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 3WA 959 655 AB 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 by UPS.

Place the printed repair order in the parcel and pack the unit so that it is protected against knocks.