Airbag control unit with part number 4N959655AC

What is the function of the airbag control unit 4N959655AC?

The airbag control unit with part number 4N959655AC is the central control module for the occupant safety system (SRS) in Lamborghini Urus S and Performante models from model year 2022 onward. It analyzes data from the acceleration sensors and decides, within milliseconds, whether to deploy airbags and activate seatbelt pretensioners.

As an OEM original part, this module is responsible for activating the passive safety systems in the event of a collision. It continuously receives signals from various crash sensors distributed throughout the vehicle to detect the type and severity of an impact.

Based on this data, the control unit ignites the appropriate airbag gas generators and activates the seatbelt pretensioners to provide optimal protection for occupants. After a crash, the device permanently stores the crash data, which triggers a safety-related immobilization.

Why does the control unit 4N959655AC fail?

The most common reason for requiring repair of the control unit 4N959655AC is the storage of crash data after a collision. In addition, internal electronic faults—such as faulty contacts or breaks on the circuit board—can also lead to complete failure or communication issues.

Following a collision, even minor ones, an irreversible error message ("crash data stored") is recorded in the control unit's internal memory. This lockout is intentionally designed by the manufacturer to prevent further use of a potentially damaged unit, while still allowing specialized technicians to perform repairs.

Electronic failures are another frequent cause. These include component defects on the circuit board, cold solder joints, or fractures in the conductive traces. Such hardware problems can arise due to aging, vibrations, or moisture, often resulting in disrupted communication with other vehicle systems.

In rare cases, external disturbances—for example, a blocked blower motor—can also affect the airbag control unit’s electronics and cause malfunctions.

Although the control unit’s design is based on the VW Group platform and shares similarities with parts like 4N0959655N (e.g., Audi A7 C8), it is not directly interchangeable. The exact part number 4N959655AC is essential for proper operation in the Lamborghini Urus.

How do you recognize a defect in the 4N959655AC?

A defective airbag control unit 4N959655AC almost always manifests as a permanently illuminated airbag warning light on the instrument cluster. Additionally, the unit may become unreachable via the OBD interface, causing diagnostic tests at a workshop to fail.

The primary and unmistakable sign is the red airbag warning light, which does not extinguish after starting the engine—indicating a serious fault in the safety system that could compromise the vehicle’s roadworthiness.

Another clear symptom is the lack of communication. When a workshop attempts to read the fault memory, the diagnostic tool often reports “control unit not responding” or “communication impossible.” This is typical of an internal fault or a crash-data lockout.

If error codes can still be retrieved, entries such as “internal control unit error” or “crash event stored” directly point to a malfunction within the module itself, confirming the need for repair or reset.

In which vehicles is the 4N959655AC installed?

The airbag control unit with part number 4N959655AC is specifically designed for high-performance models within the Volkswagen Group. At Airbag24, we accept this module for repair on Lamborghini Urus S and Performante models from model year 2022 onward.

Accurate assignment of this control unit is crucial for the flawless operation of the complex safety system. At Airbag24, we repair part number 4N959655AC for the following specific models:

Lamborghini Urus S (from model year 2022)

Lamborghini Urus Performante (from model year 2022)

It is vital that the part number stamped on the control unit exactly matches 4N959655AC to avoid compatibility issues. Repair ensures that the original, vehicle-specific configuration remains intact.

How is the 4N959655AC professionally repaired?

At Airbag24, repair of the control unit 4N959655AC involves professionally erasing the stored crash data and conducting a thorough hardware inspection. Defective electronic components are either refurbished or replaced to restore full functionality of the original device.

After submitting the removed control unit to Airbag24, the repair process begins with an in-depth analysis. First, the module’s internal memory is read to identify the nature of the fault—typically stored crash data.

The core of the repair is resetting the memory to factory settings. This removes accident‑induced lockouts, restoring the control unit to full functionality. The process requires specialized equipment and expertise and is often successful without subsequent re‑coding in the vehicle.

At the same time, the circuit board is inspected for visible and measurable hardware defects such as cold solder joints, faulty contacts, or damaged components. If any faults are detected, they are professionally repaired. No simulators or “dummies” that could compromise safety are used.

Finally, the repaired control unit undergoes a functional test before being returned to you. We provide a 12‑month warranty on every repair.

What are the benefits of repairing 4N959655AC?

Repairing the original airbag control unit 4N959655AC offers significant cost savings—up to 70% compared to an expensive new part from the manufacturer. Additionally, the original vehicle coding is preserved, often eliminating the need for time‑consuming reprogramming.

The greatest advantage lies in its cost‑effectiveness. A new OEM control unit for a Lamborghini model is extremely expensive. Repair provides a budget‑friendly yet technically sound alternative that restores full safety.

Since the original, vehicle‑specific control unit is repaired, complicated programming or coding—typically required for a new part—is usually unnecessary. The refurbished module can generally be reinstalled using a simple plug‑and‑play approach, saving both time and workshop costs.

With a 12‑month warranty on the completed repair, you gain added confidence in the quality of the restoration. You’re also choosing a sustainable solution that conserves valuable electronic resources.

What shipping options does Airbag24 offer?

To send your control unit to Airbag24, you can deliver it yourself free of charge or ship it via courier. Alternatively, we offer convenient UPS pickup from your preferred location. Returns are shipped free of charge via UPS Standard, with optional Express delivery and/or cash on delivery.

For sending your unit to us, you have two straightforward options: you can mail the package yourself or bring it in person. Alternatively, you can book UPS pickup through our portal, allowing us to collect the package directly from your home or workshop.

After successful repair, we provide flexible return‑shipping options. UPS Standard shipping is free of charge.

If you prefer faster delivery, UPS Express is available. Both Standard and Express shipping can also be arranged with cash on delivery upon request.

Of course, you may also choose to pick up your repaired control unit in person at our facility.