Airbag control unit with part number A2058600802

What is the function of the airbag control unit A2058600802?

The airbag control unit A2058600802 is the central control module for the occupant safety system (SRS), specifically in the Mercedes-Benz C-Class T‑Model of the S205 series. It continuously monitors all safety‑related components, processes signals from crash sensors, and ensures that, in the event of an accident, the airbags and seatbelt pretensioners are deployed precisely and reliably.

As the “brain” of the passive safety system, this module decides within milliseconds whether to activate the restraint systems. It coordinates the interaction between the acceleration sensors at the front and sides of the vehicle, as well as the seatbelt pretensioners and multi‑stage airbags. Its flawless operation is therefore crucial for passenger safety.

The complex electronics inside ensure that false activations are avoided and that the protection systems only deploy upon a genuine impact. Its task is to assess the severity of the crash and initiate the appropriate rescue measures.

Why does the airbag control unit A2058600802 fail?

The most common cause of failure for the A2058600802 is internal electronic faults on the circuit board, often indicated by error codes such as B1BC7-49 or B220700. Another frequent issue is the storage of crash data after an accident, which blocks the device’s functionality for safety reasons and requires professional reprogramming.

A typical defect involves hardware components like microcontrollers, processors, or capacitors. These parts are subject to aging and thermal stress, leading to internal malfunctions. Such defects are often logged in the fault memory as “severe internal fault” (B220700) or “internal electronic fault in the SRS control unit” (B1BC7-49).

After a collision, the control unit stores so‑called crash data. This information permanently locks the module to prevent reuse without expert diagnostics. The lock can only be lifted through specialized repair, during which the data is erased and the unit is reset to factory settings.

Moisture damage can also affect the sensitive electronics, causing corrosion on the circuit board, disrupting communication, or even resulting in complete failure.

Defects in this control unit may also occur with equivalent or similar part numbers, including A2058600202, A2059008618, A2058600585, A2058600685, and A2058600185.

How do you recognize a defect in the A2058600802?

A defect in the A2058600802 control unit is primarily signaled by a constantly illuminated or intermittently flashing airbag warning light on the instrument cluster. Often, communication between a diagnostic tool and the control unit becomes impossible, significantly complicating troubleshooting in the workshop.

The most obvious symptom is the active SRS or airbag warning light, indicating to the driver that the restraint system is either non‑functional or only partially operational—and may fail to deploy in the event of an accident.

Another clear sign is when the workshop can no longer read the control unit. Diagnostic tools receive no response from the module, pointing to a severe internal fault or a total breakdown of the communication electronics.

Error codes stored in the fault memory, such as B1BC7-49 or B220700, directly indicate an internal malfunction. Occasionally, specific messages like “Driver airbag cannot be deactivated” appear, caused by a blockage due to stored crash data.

In which vehicles is the A2058600802 control unit installed?

The A2058600802 control unit is primarily designed for the Mercedes-Benz C-Class T‑Model of the S205 series (model years 2014–2021). However, similar or interchangeable variants may also be used in the W205 series (sedan and coupe), expanding compatibility.

At Airbag24, we repair the A2058600802 airbag control unit for the following model:

Mercedes-Benz C-Class S205 T‑Model (2014–2021)

Due to their close technical relationship, repairs are often possible for the sedan (W205) and the coupe as well, which utilize similar control unit architectures.

How is the A2058600802 professionally repaired?

A professional repair of the A2058600802 includes analyzing the electronics, replacing defective components such as microcontrollers or capacitors, and reprogramming the unit while erasing crash data. This process restores full functionality and offers significant cost savings compared to purchasing a new part, backed by a 12‑month warranty.

After being sent to Airbag24, the control unit undergoes a standardized repair process. First, a comprehensive diagnosis is performed on specialized test benches to identify the exact cause of the fault—whether it’s a hardware defect or stored crash data.

Next, faulty electronic components on the circuit board are replaced with new, high-quality parts. At the same time, the device’s software is reprogrammed, and any existing crash data is completely erased, restoring the module to its factory settings.

Repair is a proven, sustainable solution. It’s significantly more cost-effective than purchasing a new part, which often ranges from 500 to 1,000 euros, whereas a repair can be completed for a fraction of that price. We provide a 12-month warranty on every repaired unit.

What shipping options does Airbag24 offer?

For repairing your control unit, Airbag24 provides flexible and secure shipping solutions. You can either return the removed unit yourself at no charge or arrange a convenient UPS pickup. Return shipping is standardly free via UPS and can be upgraded to express or cash-on-delivery upon request.

For outbound shipping, you have two options: either send the package yourself or book a hassle-free UPS pickup directly from your preferred location, such as your home or workshop.

Following successful repair, we offer several return‑shipping options:

Free UPS standard delivery (1–3 business days)

UPS express delivery (1–2 business days)

UPS standard delivery with cash-on-delivery (1–3 business days)

UPS express delivery with cash-on-delivery (1–2 business days)

Of course, you’re also welcome to pick up the repaired control unit in person at our facility.