Airbag control unit with part number A2C30469900

What is the function of the airbag control unit A2C30469900?

The airbag control unit A2C30469900, manufactured by Bosch/Continental, serves as the central control module for the passive safety system (SRS) in the second-generation Ford Ka (RU8, 2008–2016). It processes data from crash sensors and ensures precise deployment of airbags and seatbelt pretensioners in the event of a collision.

As the “brain” of the restraint system, this SRS ECU (Supplemental Restraint System – Electronic Control Unit) continuously monitors all connected components. It guarantees that the system remains operational at all times and logs internal faults or system states. This control unit is technically identical to the original Ford OEM part number 51925901.

The electronics are specifically designed for the Ford Ka Mk2 vehicle architecture and communicate via the CAN bus with other vehicle control modules, such as the instrument cluster, to display warning messages.

Why does the A2C30469900 control unit fail?

The most common cause of failure for the A2C30469900 control unit is the storage of crash data after an airbag or seatbelt pretensioner deployment. Additional defects arise from moisture ingress or the natural aging of electronic components, leading to internal hardware malfunctions.

Following a crash, the control unit self‑locks for safety reasons by recording an irreversible fault entry (crash event) in its internal memory. This is a manufacturer‑specified protective feature, not a software error. The module then becomes blocked and must be professionally reset.

Besides stored crash data, hardware failures on the circuit board can also be responsible. Aging or moisture exposure may cause components like capacitors to fail or conductive traces to corrode, resulting in total system failure or communication issues.

This control unit is also known under the Ford part number 51925901. On the used‑parts market, equivalent variants with numbers 53284384, 1553992, or 51805046 can be found, but they are equally prone to the same defects.

How do you recognize a defect in the A2C30469900?

A defect in the A2C30469900 control unit primarily manifests as a permanently illuminated or flashing airbag warning light on the instrument cluster. Often, the control unit cannot be accessed by diagnostic tools (no communication), and in some cases, the odometer display may also flash.

The most noticeable symptom is the active airbag warning light, indicating a critical fault in the restraint system that requires immediate inspection. In this state, the system is non‑functional.

Another clear sign is complete loss of communication. If the workshop can no longer access the SRS module via the OBD interface, this strongly suggests an internal fault within the control unit itself.

In addition, a flashing odometer display may appear. This symptom is specific to vehicles on this platform and points to a communication conflict within the vehicle’s electrical network, often triggered by the defective airbag control unit.

In which vehicles is the A2C30469900 installed?

The airbag control unit A2C30469900 is specifically designed for the second-generation Ford Ka (model RU8), produced between 2008 and 2016. In particular, the widely used 1.2‑liter gasoline engine is frequently equipped with this module.

At Airbag24, we repair part number A2C30469900 as well as compatible variants for the following model:

Ford Ka 2 (model RU8), years 2008–2016

The repair applies to all engine configurations within this series, as the underlying safety system architecture remains identical. However, analyses reveal a higher incidence of defects in the Ford Ka 1.2‑liter version with 51 kW (69 hp).

What are the advantages of repairing versus replacing with a new unit?

Repairing the original control unit offers significant cost savings compared to purchasing a new one. Since the vehicle‑specific configuration is preserved, no time‑consuming reprogramming is required at the workshop, saving both time and additional expenses.

From a financial standpoint, refurbishment is the most economical solution. A new unit is often disproportionately expensive, while used control units carry the risk of being defective themselves or already containing stored crash data.

A key technical advantage is the preservation of the original coding. Because your control unit is repaired rather than replaced, all data—including the Vehicle Identification Number (VIN)—remains intact. After installation, the device can be used immediately without further programming (plug-and-play).

Additionally, repair is a sustainable and resource‑efficient alternative. Airbag24 provides 2 years’ statutory liability for defects on professional refurbishment—something typically not offered for used parts sourced from scrapyards.

How is the A2C30469900 control unit professionally repaired?

At Airbag24, repairs follow a rigorous, professional process. Upon receipt, the A2C30469900 control unit undergoes a comprehensive electronic diagnostic to pinpoint the exact cause of the fault. Subsequently, crash data is reset, and any defective components are replaced by qualified technicians.

First, the control unit must be removed from the vehicle. In the Ford Ka RU8, it is typically located beneath the center console or dashboard. After removal, the unit is securely packaged and shipped to us.

In the initial repair step, our technicians read the internal fault memory to check whether crash data has been stored. This data is then completely and safely erased using specialized software and hardware. Defective electronic components, such as capacitors or damaged circuit board sections, are identified and replaced.

Following refurbishment, the control unit undergoes a final functional test to ensure communication has been restored and all system parameters are correct. You receive 2 years' statutory liability for defects on the completed repair.