Airbag control unit with part number 46475013

What is the function of Airbag Control Unit 46475013?

The airbag control unit with part number 46475013 is the central control module for the passive safety system in the Fiat Marea 185. It processes 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, thereby protecting the occupants.

This control unit, often supplied by Siemens in this vehicle series, continuously monitors all components connected to the restraint system. These include the driver and passenger airbags, side airbags (if fitted), as well as pyrotechnic seatbelt pretensioners.

Every system check performed during vehicle startup is initiated by this device. If it detects a fault in any of the circuits or in its own internal electronics, it activates the airbag warning light (SRS) to alert the driver.

Why does control unit 46475013 fail?

A common cause of failure for control unit 46475013 is the storage of crash data after an accident. Even after a minor impact, the unit locks itself internally. In addition, internal electronic faults—such as issues with memory chips, sensors, or the internal power supply—can lead to malfunctions and persistent error messages.

After the airbags or seatbelt pretensioners have been deployed, so‑called crash data is permanently stored in the control unit’s memory. This lockout prevents reuse without professional repair and cannot be cleared using standard workshop diagnostic tools.

Another typical defect is an internal hardware failure. This often manifests as the “internal control unit error” code stored in the fault memory. Such errors indicate problems with electronic components like memory chips (EEPROM/Flash), processors, or internal acceleration sensors.

How can you recognize a fault in control unit 46475013?

The most obvious symptom of a fault in control unit 46475013 is the airbag warning light on the dashboard, which remains illuminated or flashes intermittently. Additionally, error codes such as “internal error” often cannot be cleared, or the control unit becomes unreachable by diagnostic equipment altogether (communication error).

The airbag warning light (SRS lamp) directly indicates that the system has detected a fault and may not function properly in an emergency. It fails to extinguish after engine start-up as expected.

In the workshop, the fault is frequently revealed when reading the fault memory: the error reappears immediately after attempts to clear it. In some cases, communication via the OBD interface to the airbag control unit is simply impossible.

There may also be misleading error codes assigned to individual components, such as the driver airbag or seatbelt pretensioners, even though these parts are intact. The real cause then lies within the defective control unit itself.

In which vehicles is control unit 46475013 installed?

Part number 46475013 is specific to Fiat vehicles. It is used exclusively in the Fiat Marea 185 model range, which includes both the sedan and the station wagon variant (Weekend), covering both pre- and post-facelift production phases.

At Airbag24, we repair the airbag control unit with part number 46475013 for the following specific models:

Fiat: Marea 185 (model years 1996–1999) and Marea 185 Facelift (model years 1999–2003). This covers both the sedan and the Marea Weekend.

How is control unit 46475013 repaired?

The repair process includes professional diagnostics, electronic component restoration, and reprogramming of the unit. After submission, control unit 46475013 undergoes inspection, crash data is erased, faulty components are replaced, and a final functional test on a simulator ensures proper operation.

Following careful removal from the vehicle, the control unit is sent to Airbag24. Here, the process begins with an incoming inspection, during which stored error codes and any crash data are read out.

Our technicians conduct a detailed analysis of the circuit board to identify electronic defects in components such as voltage regulators, memory chips, or sensors. Defective parts are professionally replaced, and cold solder joints are reworked.

A key step is reprogramming the memory: crash data is completely removed, and the control unit is restored to factory settings. Finally, functionality is simulated on a specialized test bench to ensure that, once reinstalled, all systems operate flawlessly. We provide 2 years' statutory liability for defects on every repair.