Airbag control unit with part number 50508413

What is the function of Airbag Control Unit 50508413?

The airbag control unit with part number 50508413 is the central control module of the Supplemental Restraint System (SRS) in Alfa Romeo MiTo 955 vehicles. It processes data from acceleration and crash sensors to precisely and rapidly deploy airbags and seatbelt pretensioners in the event of a collision.

This component is crucial for the vehicle’s passive safety. In addition to its deployment function, the SRS module continuously monitors all connected system components—such as sensors, airbag modules, and seatbelt pretensioners—for proper operation.

Following a crash or upon detection of system faults, the control unit stores so‑called crash data or fault codes and activates the SRS warning light in the cockpit to alert the driver to a malfunction in the safety system.

Why does Airbag Control Unit 50508413 fail?

The most common cause of failure for control unit 50508413 is the storage of crash data after an airbag deployment. Other reasons include internal electronic malfunctions, defects in memory chips (EEPROM), or damage caused by moisture and voltage surges, all of which may necessitate repair.

After a crash, the manufacturer locks the control unit for safety reasons by permanently storing crash data in its internal memory. This is not a true malfunction but rather an intentional lockout that prevents reuse without professional inspection and reset.

Beyond accidents, age‑related defects in electronic components such as processors or memory chips can also occur. Cold solder joints or corrosion due to moisture are additional potential causes of total failure or communication issues over the CAN bus.

How do you recognize a defect in Control Unit 50508413?

A defect in Airbag Control Unit 50508413 primarily manifests as a constantly illuminated or flashing airbag warning light (SRS lamp). Additionally, specific fault codes such as B1111, 65535, or 93F9 may be read out, directly indicating an internal control unit error.

The most obvious sign is the persistently lit SRS indicator on the instrument cluster, signaling that the restraint system is not functioning properly and might fail to deploy in the event of a crash.

During workshop diagnostics, specific fault codes are often stored in the fault memory. Typical entries for this control unit include “B1111 (control unit defective),” “65535 (control unit defective),” “93F9 (internal error),” or model‑specific codes like “B01” in the Alfa Romeo context.

In severe cases, communication with the diagnostic tool becomes impossible. The control unit no longer responds to queries, pointing to a serious internal defect or a problem with the CAN‑bus connection.

In which vehicles is Airbag Control Unit 50508413 installed?

The airbag control unit with part number 50508413 is specifically fitted in the Alfa Romeo MiTo 955 series. This covers the entire production period from 2008 to 2018, including various facelift versions and the high‑performance Quadrifoglio Verde (QV) model.

At Airbag24, we professionally repair control unit 50508413 for the following models:

Alfa Romeo MiTo (series 955, 2008–2013)

Alfa Romeo MiTo Facelift (series 955, 2013–2016)

Alfa Romeo MiTo Facelift (series 955, 2016–2018)

Alfa Romeo MiTo QV (Quadrifoglio Verde, series 955)

How does the repair of Control Unit 50508413 proceed?

The repair focuses on the electronic refurbishment of the original unit. After removal and shipment, the control unit is analyzed, stored crash data is erased, and any defective internal components are replaced. Finally, full functionality is verified, making it ready for reinstallation.

Before removal—which typically takes place in the center console beneath the handbrake lever—the vehicle battery should be disconnected for at least 10 minutes to prevent unintended airbag deployment.

Upon submission to Airbag24, a detailed technical analysis follows. The core of the repair involves safely erasing crash data and resetting the internal EEPROM memory to factory settings. If additional electronic defects are present, they are addressed at the component level.

Following successful repair and a final functional test, the control unit is fully operational again. It can be reinstalled in the vehicle without further coding. We provide 2 years' statutory liability for defects on every repair.

What are the advantages of repairing versus buying a new unit?

The key advantage of repair is the substantial cost savings—up to 90% compared to a new part, which often costs between €400 and €750. Additionally, there’s no need for time-consuming re‑programming of the control unit, as the original vehicle configuration is preserved.

A refurbished original control unit is “plug-and-play.” It simply gets reinstalled, and the fault memory in the vehicle is cleared. With a new part or a used unit from another vehicle, expensive and labor‑intensive programming at a specialized workshop would be unavoidable.

Repair is not only economical but also sustainable, helping to avoid electronic waste and conserving valuable resources that would otherwise be required to manufacture a new component.