Airbag control unit with part number 285001235

What is the function of Airbag Control Unit 285001235?

The airbag control unit with part number 285001235 is the central control module for the passive safety system (SRS) in the Mitsubishi Carisma DA. It continuously analyzes data from crash sensors and is responsible for precisely deploying the airbags and seatbelt pretensioners at the right moment in the event of a collision.

As the “brain” of the restraint system, this module—often manufactured by suppliers such as Denso—determines occupant safety. It monitors all connected components, including sensors, airbag modules, and seatbelt pretensioners, to ensure they are functioning properly.

In the event of a collision, it processes incoming signals and activates the necessary restraint devices. After deployment, the unit stores so‑called crash data, which triggers a system lockout, necessitating repair or replacement.

Why does Airbag Control Unit 285001235 fail?

The most common cause of failure is the storage of crash data following an accident, which locks the control unit. Other faults arise from electronic malfunctions such as short circuits, moisture damage, or undervoltage caused by a defective battery or alternator.

Following a crash, the control unit becomes hardware‑locked. This safety feature prevents uncontrolled re‑deployment but renders the device unusable without professional repair. Erasing this stored data is a critical step in the repair process.

External factors like penetrating moisture can lead to corrosion on the circuit board and component failure. Similarly, voltage spikes or persistent undervoltage can permanently damage sensitive electronics, particularly memory chips.

These fault patterns are not limited to part number 285001235; they also occur in technically related control units, such as numbers 285001286 and 285001290, which are installed in similar vehicle models.

How do you recognize a defect in Control Unit 285001235?

A defect typically manifests as a constantly illuminated or flashing airbag warning light (SRS indicator) on the dashboard. Often, the control unit can no longer be read by diagnostic equipment, or error codes such as B1000 or “internal control unit error” are logged.

The clearest sign is the active SRS warning light, indicating that the entire airbag system is disabled and offers no protection in the event of a crash. The vehicle should be inspected immediately at a specialized workshop.

Another clear symptom is the lack of communication: when a workshop attempts to read the fault memory, the diagnostic tool receives no response from the airbag control unit, pointing to a severe internal hardware malfunction.

If communication remains possible, specific error codes are often recorded. Codes like B1000, or textual descriptions such as “component defective” or “internal error,” directly indicate a malfunction within the control unit itself. In some cases, the engine check light may also flash as an accompanying symptom.

In which vehicles is Control Unit 285001235 installed?

The airbag control unit with part number 285001235 is specifically designed for models in the Mitsubishi Carisma DA series. At Airbag24, we professionally restore this control unit for all associated model variants and production years, ensuring full functionality of the safety system.

At Airbag24, we repair part number 285001235 for the following specific Mitsubishi models:

Mitsubishi Carisma DA1A (model years 1995–1999)

Mitsubishi Carisma DA2A (model years 1999–2002)

Mitsubishi Carisma DA2A (model years 2002–2004)

It is crucial that the part number of the defective unit matches exactly. Related part numbers, such as 285001286 and 285001290—which appear in this vehicle family—are also covered by our repair service.

How is Control Unit 285001235 repaired?

After being sent to Airbag24, the control unit undergoes systematic diagnostics on specialized test benches. Stored crash data is then erased, defective electronic components are replaced, and all functions are restored. Each repair concludes with a final test and 2 years' statutory liability for defects.

First, it is advisable to confirm at a specialized workshop that the fault originates from the control unit itself, rather than from external components such as sensors or wiring. Following removal, the defective unit is securely packaged and shipped to us.

At Airbag24, a detailed analysis is performed to pinpoint the exact cause of the fault. Our technicians use specialized test benches that simulate the vehicle’s operating environment, enabling precise diagnostics.

The actual repair process includes professionally erasing crash data and replacing all defective components on the circuit board. Following successful repair, the control unit undergoes a comprehensive functional test to ensure it meets the manufacturer’s specifications.