Airbag control unit with part number 5WY79340

What is the function of the airbag control unit 5WY79340?

The airbag control unit with part number 5WY79340, also known under references 25820724 and 5WY79340-95160, is the central control unit for the passive safety system. It continuously monitors signals from the airbag sensors and seatbelt pretensioners, and activates the restraint systems in the event of a crash. After activation, it stores crash data, which locks the system for safety reasons.

As the “brain” of the restraint system, its primary task is to analyze data from acceleration and pressure sensors in the vehicle in real time. If the control unit detects a collision requiring deployment, it sends ignition pulses to the corresponding airbags and seatbelt pretensioners within milliseconds.

A critical function is storing crash data after an accident. This process is irreversible and serves safety purposes to prevent accidental re‑ignition. The control unit indicates this status by keeping the airbag warning light illuminated, and must be professionally reset or repaired to resume normal operation.

What defects occur in the 5WY79340?

The most common causes of failure for the 5WY79340 control unit are stored crash data following an accident, which locks the module, as well as internal electronic hardware defects. These include damaged SMD components, faulty voltage regulators, or blown transistors on the circuit board, requiring component‑level repair.

The primary reason for failure is the storage of crash or accident data. This is not a defect in the traditional sense but rather a manufacturer‑specified safety feature. Once activated, the module remains locked and must be reset by a qualified workshop—often referred to as a “module reset.”

In addition, purely electronic faults may occur. These encompass microcontroller failures, damage to conductive traces caused by moisture or short circuits, and defective MOSFETs responsible for driving the ignition circuits. Such hardware issues disrupt communication with the device or result in persistent internal error codes. Identical fault patterns are observed in the equivalent control units numbered 25820724 and 5WY79340-95160.

How do you recognize a defect in the airbag control unit?

A defect in the 5WY79340 control unit typically manifests unmistakably through a permanently illuminated airbag warning light on the dashboard. Another clear symptom is the lack of communication with the diagnostic tool, preventing the reading of error codes. DTCs stored in the fault memory indicating an internal control unit malfunction confirm the defect.

The most noticeable sign is the red airbag warning light that fails to extinguish after starting the engine. This alerts the driver that the entire restraint system is disabled and would not deploy in the event of a crash.

In the workshop, the defect often becomes apparent when the diagnostic tester cannot establish a connection to the airbag control unit. The module does not respond to requests, making further troubleshooting impossible and pointing directly to a hardware fault or internal lockout.

In which vehicles is the 5WY79340 control unit installed?

The airbag control unit with part number 5WY79340, along with its related references 25820724 and 5WY79340-95160, is designed specifically for one vehicle model. At Airbag24, we professionally repair this control unit for the Opel GT Roadster manufactured between 2007 and 2009.

Accurate matching is crucial for the proper functioning of the safety system. This control unit is found exclusively in the following model:

Opel GT Roadster (model years 2007–2009)

How does the repair of the 5WY79340 proceed at Airbag24?

The repair of the 5WY79340 at Airbag24 follows a structured process. Upon receiving the removed control unit, our technicians perform a comprehensive incoming inspection. Depending on the nature of the fault, either the crash data is professionally reset or defective electronic components on the circuit board are replaced. Final functional tests ensure full operational readiness, backed by 2 years’ statutory liability for defects.

First, the control unit should be removed by a specialized workshop. After sending it to Airbag24, a diagnosis is carried out to determine the exact cause of the fault using specialized testing equipment.

If only crash data is present, the module is restored to factory settings. In cases of electronic defects, damaged components such as voltage regulators, transistors, or other SMD parts are carefully replaced, and solder joints are reworked.

After successful repair, the control unit undergoes a final communication test to ensure flawless vehicle compatibility and the ability to clear all fault codes. We provide 2 years' statutory liability for defects on every repair.