Airbag control unit with part number 285001552

What is the function of the airbag control unit 285001552?

The Bosch airbag control unit with part number 285001552, also known as 0285001552, is the central control unit for the occupant protection system in the Ford Focus Mk2. It processes signals from crash sensors to precisely deploy airbags and seatbelt pretensioners in the event of a collision, and is typically installed in the center tunnel.

As the brain of the passive safety system, this control unit continuously monitors and evaluates data from the vehicle’s acceleration and pressure sensors. If it detects a collision severe enough to endanger occupants, it sends ignition pulses to the appropriate airbags and seatbelt pretensioners within milliseconds.

The unit often also carries the Ford reference number 4M5T14B056BF. Due to its safety-critical function, flawless operation is essential. It is usually mounted in the tunnel area next to the gearshift lever—a position intended to protect it from minor damage.

Why does the control unit 285001552 fail?

A malfunction of the control unit 285001552 is frequently caused by stored crash data following an accident, which blocks further functionality. Other causes include internal electronic faults, moisture damage due to its installation location in the vehicle, or pre-existing damage resulting from improper repair attempts.

After an accident in which the airbags have deployed, the control unit stores so‑called crash data. For safety reasons, these data lock the module and prevent reuse without professional reconditioning. This condition is often displayed as an “internal error” in the fault memory.

The installation location in the center tunnel makes the unit vulnerable to moisture, such as from spilled beverages. Ingressing liquid can lead to corrosion on the circuit board and failure of electronic components. Internal defects in parts like processors or memory modules may also occur without any external influence.

How do you recognize a defect in the 285001552?

A typical sign of a defect in the control unit 285001552 is a permanently illuminated or flickering airbag warning light on the instrument cluster. Often, communication with the control unit via a diagnostic tool cannot be established, or error codes such as “internal error” are logged.

The primary symptom is the activated airbag warning light, indicating to the driver that the safety system is either non‑functional or only partially operational. The fault persists even after clearing the fault memory, or reappears immediately.

Another clear indication is the inability to perform diagnostics. When a workshop attempts to read the control unit through the OBD2 interface, communication fails—the unit does not respond to requests, suggesting a serious internal defect.

Stored crash data or specific error codes pointing to an internal fault, a defect in the side‑impact sensor circuit, or error 1515 (in similar models) are also reliable indicators. Customers also report accompanying symptoms, such as the dashboard illumination when locking the vehicle.

In which vehicles is the 285001552 installed?

The Bosch airbag control unit 285001552 is primarily used in second‑generation Ford Focus models (Mk2). At Airbag24, this part number is offered for repair in the Ford Focus 2 ’04 series and the ’04 facelift model—both produced between 2004 and 2007—as well as the Turnier (station wagon).

At Airbag24, repair of the control unit 285001552 is available for the following vehicle models:

Ford:

Focus 2 ’04 (model years 2004–2007)

Focus 2 ’04 Facelift (model years 2004–2007)

Focus 2 Turnier (station wagon)

How does the repair of the 285001552 work at Airbag24?

Professional repair at Airbag24 begins with diagnosing the removed control unit to verify the exact fault. Defective electronic components are then replaced, and stored crash data are erased. Following a comprehensive functional test, the refurbished unit is returned to the customer.

Upon receipt of the control unit at Airbag24, an initial inspection is performed. It is recommended to read the fault memory before removal and attach the shipment’s test report. This speeds up analysis and ensures that the fault lies within the device itself.

The next step involves actual refurbishment: technicians erase stored crash data and replace all defective electronic components. Throughout this process, the original functionality and vehicle coding remain fully intact, avoiding the need for time‑consuming reprogramming after installation.

Finally, the control unit is tested on a test bench to ensure the proper functioning of all systems. Each repair comes with 2 years' statutory liability for defects. Compared to a new part, a repair is not only more cost-effective but also resource-efficient and helps preserve your vehicle’s value.