Airbag control unit with part number A2479018801

What is the function of the airbag control unit A2479018801?

The airbag control unit with part number A2479018801 serves as the central safety module in modern Mercedes-Benz compact models. It processes signals from vehicle sensors and, in the event of a crash, precisely and within seconds deploys the airbags and seatbelt pretensioners to protect occupants.

As the brain of the passive safety system, this control unit continuously monitors all connected components—from the crash sensors at the front and sides of the vehicle to the individual airbag modules and seatbelt pretensioners—ensuring that the entire restraint system remains fully operational at all times.

This component is also known under alternative original part numbers such as A1779000304, A1779027906, and A1779006604. Its technical foundation originates from Bosch, as evidenced by reference number 0285015019. These numbers are interchangeable and denote functionally identical control units.

Why does the control unit A2479018801 fail?

The most common cause of failure for the control unit A2479018801 is internal electronic defects on the main circuit board. Such hardware malfunctions can arise from component aging or thermal stress, causing the device to lose its ability to perform its functions correctly, which is indicated by the airbag warning light.

Since the control unit can be repaired electronically, these defects typically involve localized issues in specific components. Specialized workshops can identify and replace these faulty parts, restoring the device’s full functionality.

Therefore, replacing it with a new unit is often unnecessary. Repair offers a cost-effective and sustainable alternative, ensuring the original functionality of the control unit without compromising safety.

How do you recognize a defect in the A2479018801?

A defective airbag control unit A2479018801 primarily manifests as a permanently illuminated airbag warning light on the instrument cluster. Additionally, an error message may appear on the vehicle’s display. Reading the fault memory often reveals the entry “Control unit internal defect,” indicating a hardware issue.

The most noticeable symptom is the persistently lit red airbag warning light. It does not extinguish after starting the vehicle, signaling that the entire occupant protection system is disabled and will not function in the event of a crash.

In more severe cases, the control unit may no longer communicate with a diagnostic tool. Attempts to read the fault memory via the OBD interface will fail because the unit no longer responds to requests—an unmistakable sign of a serious internal malfunction.

In which vehicles is the A2479018801 installed?

The control unit A2479018801 is installed in Mercedes-Benz’s compact car generation. At Airbag24, we repair this component for the Mercedes-Benz A-Class W177, B-Class W247, and CLA W118. Our expertise covers all variants and alternative part numbers within this control unit family.

Compatibility extends to the following models built on the same technical platform:

Mercedes-Benz A-Class (W177 series) from model year 2018 onward

Mercedes-Benz B-Class (W247 series)

Mercedes-Benz CLA-Class (W118 series)

How is the A2479018801 professionally repaired?

After being sent to Airbag24, the control unit A2479018801 undergoes a rigorous repair process. First, an initial inspection and detailed analysis are conducted on specialized test benches to determine the exact cause of the fault. Subsequently, defective electronic components are expertly replaced. All repairs come with a 12-month warranty.

The repair is performed at the component level. Our technicians locate the faulty parts on the circuit board and replace them with high-quality new spare parts. This process fully restores the original functionality and reliability of the control unit.

Following restoration, each control unit undergoes a comprehensive final inspection. Its proper operation is verified in a simulated driving environment to ensure all systems function flawlessly and that the unit is immediately ready for use upon installation.

What shipping options does Airbag24 offer?

Airbag24 provides flexible and secure shipping options. You can send your defective control unit free of charge yourself or arrange a convenient UPS pickup at a location of your choice. Return shipping after repair is also free via standard UPS delivery. For urgent cases, express and cash-on-delivery options are available.

For sending the unit to us, you have two simple options: either pack the control unit securely and ship it to us yourself, or arrange a scheduled UPS pickup directly through our system.

The return shipment of your repaired unit is free of charge via UPS as standard. If you need it sooner, you can opt for UPS Express shipping. Additionally, we offer cash-on-delivery as an option for both shipping methods. Of course, you can also pick up the unit in person at our facility.