Airbag control unit with part number 959103N250

What is the function of the airbag control unit 959103N250?

The airbag control unit with part number 95910-3N250 is the central control module for the occupant safety system (SRS) in the Hyundai Equus LZ/YJ. It is also listed under the Siemens/VDO number 5WK42995. Its primary task is to process crash sensor data and trigger the airbags and seatbelt pretensioners within seconds during a collision.

As the brain of the safety system, this Airbag Control Unit (ACU) continuously monitors all connected components, such as crash sensors, seat occupancy mats, airbags, and seatbelt pretensioners. It ensures that the system operates flawlessly when needed.

This specific control unit is designed for the first-generation electronic architecture of the Hyundai Equus (circa 1999–2009) and is essential for its proper safety functionality.

What defects occur in 95910-3N250?

The most common defects of the 95910-3N250 control unit include stored crash data after an accident that locks the system, as well as internal electronic faults. The latter often manifest as error code B1620 or complete communication failure. Defects in components such as memory ICs or voltage regulators are also typical causes.

After a crash or activation of seatbelt pretensioners, crash data is permanently saved in the internal memory (EEPROM/Flash). The control unit then locks itself, and the airbag warning light remains illuminated. This data cannot be erased using conventional diagnostic tools.

A frequent fault reported by Hyundai is “B1620 – internal control unit error.” This code indicates a hardware defect inside the device, such as a faulty microcontroller, memory IC, or other critical board components.

Another serious issue is total communication loss. Although other vehicle control units can still be accessed via the OBD interface, the airbag control unit no longer responds. This is usually the result of severe electronic damage.

Electronic failures caused by aging, overvoltage, or improper power supply can also lead to complete system failure. Voltage regulators, driver ICs, or capacitors are often affected. Corrosion from moisture can likewise damage circuit traces or connector pins, disrupting functionality.

How do you recognize a defect in the 959103N250 control unit?

A defective 95910-3N250 control unit almost always shows a permanently illuminated airbag warning light on the instrument cluster. Additionally, the diagnostic tool may fail to establish communication with the airbag control unit. The fault memory frequently stores entries like “B1620 – internal control unit error.”

The primary and unmistakable symptom is the active SRS warning light, which does not turn off after starting the vehicle—indicating a persistent, safety-critical fault in the system.

In the workshop, the defect often becomes apparent when communication with the control unit cannot be established. Attempts to read fault codes or perform a system diagnosis fail because the module does not respond to requests.

If diagnostics are possible, specific, non‑erasable error codes such as “internal control unit error” or the Hyundai‑specific code B1620 directly point to an internal hardware fault requiring component‑level repair.

In which vehicles is the 959103N250 control unit installed?

The airbag control unit 95910-3N250 is specifically designed for the first-generation Hyundai Equus (LZ/YJ series), produced roughly between 1999 and 2009. At Airbag24, we offer professional repair services for this control unit, which is also known under the Siemens/VDO number 5WK42995 and installed in this vehicle model.

At Airbag24, we provide expert repair of part number 959103N250 for the following vehicle model:

Hyundai Equus (LZ/YJ series, manufactured circa 1999–2009)

How does repair work at Airbag24?

At Airbag24, repairing the 95910-3N250 control unit involves comprehensive diagnostics, professional erasure of crash data, and replacement of defective electronic components. After repair, the unit is tested on a bench to ensure full functionality and can then be reinstalled plug-and-play.

Following removal and shipment to Airbag24, the control unit undergoes an initial incoming inspection. Technicians check for external damage such as corrosion and test electrical functionality on a specialized test bench.

The most common repair step is resetting the crash data. For this, the internal memory chip (EEPROM/Flash) is read out, and the crash lock is selectively removed, while preserving the original vehicle coding intact.

If an electronic fault such as error B1620 is present, defective components on the circuit board are identified and replaced with new, high-quality parts. This includes, for example, memory ICs, processors, or voltage regulators.

Subsequently, each repaired control unit undergoes rigorous final testing on a test bench. Only when all functions are fully operational is it approved for return shipment. The repair is plug-and-play and comes with a 12-month warranty.

What are the benefits of repairing the 959103N250?

Repairing the 95910-3N250 control unit is a cost-effective and sustainable alternative to expensive new purchases. You save significantly compared to a brand-new part, retain the original vehicle-specific coded unit, and receive a repair backed by a 12-month warranty. The plug-and-play solution also eliminates the need for time-consuming re-coding.

The financial advantage is substantial. Repair costs amount to only a fraction of the price of a new control unit from the manufacturer, providing significant relief to workshops and vehicle owners alike.

Since the original unit is repaired, all vehicle-specific data—such as the Vehicle Identification Number (VIN) and coding—remain intact. There is no longer any need for costly and labor-intensive reprogramming of a new control unit at an authorized service center.

Repair is a fast and reliable solution. After refurbishment, the control unit is returned ready for installation (plug-and-play). Additionally, a 12-month warranty is provided on the completed repair.

What shipping options are available?

You can either send your defective control unit to Airbag24 yourself at no charge, or arrange a convenient UPS pickup. For return shipments, you have access to free standard and paid express options, both with cash-on-delivery service. Personal collection at our workshop is also possible.

For outbound shipping, you have two choices: you can send the package to us yourself free of charge, or use the UPS pickup service, which collects the package from a location of your choosing.

For returning the repaired unit, we offer the following options:

- UPS Standard Shipping (1–3 business days), free of charge.

- UPS Express Shipping (1–2 business days).

- UPS Standard Shipping with Cash-on-Delivery (1–3 business days).

- UPS Express Shipping with Cash-on-Delivery (1–2 business days).

- Self-collection directly at our premises.