Airbag control unit with part number 4G0959655A

What is the function of the airbag control unit 4G0959655A?

The airbag control unit with part number 4G0959655A is the central control module for the entire occupant safety system (SRS) in vehicles such as the Audi A7 and RS7 of the C7 generation. It processes signals from crash sensors and, within milliseconds, decides whether to deploy airbags and tighten seat belts to protect occupants in the event of a collision.

This control unit is specifically designed for models manufactured between 2010 and 2018, covering both the original C7 platform and its facelifted versions.

As the “brain” of the safety system, it continuously communicates with other vehicle systems to ensure constant operational readiness. If this component fails, the vehicle’s passive safety features are no longer functional.

Why does the control unit 4G0959655A fail?

The most common causes of failure for the control unit 4G0959655A include stored crash data after an accident that locks the unit, as well as internal defects in electronic components. Complete communication failure—where the control unit becomes unresponsive—is another typical issue requiring repair.

Following a collision, even minor ones, the control unit stores so‑called crash data. This information prevents further system operation and permanently activates the airbag warning light. Clearing this data at a specialized service center is necessary to restore functionality, provided there are no additional malfunctions.

Another frequent cause is hardware damage on the circuit board. Electronic components such as processors, memory chips, or capacitors may fail due to age or external factors, leading to internal errors that necessitate repairing the affected parts.

How can you recognize a defect in the 4G0959655A?

A defect in the airbag control unit 4G0959655A typically manifests through clear symptoms. The most obvious sign is a constantly illuminated airbag warning light on the instrument cluster. Additionally, the control unit may become inaccessible via diagnostic equipment, making fault analysis at a workshop impossible.

The activated airbag warning light serves as the primary alert for the driver. It remains lit after starting the engine, indicating that the occupant safety system (SRS) is not functioning properly.

Another critical symptom is loss of communication. When a workshop attempts to read the fault memory, no connection can be established with the control unit, pointing to a severe internal malfunction.

Ultimately, such a defect results in complete failure of the protective functions. In the event of an accident, neither airbags nor seatbelt pretensioners will deploy, posing a significant safety risk.

In which models is the 4G0959655A installed?

The airbag control unit with part number 4G0959655A is exclusively fitted in Audi’s high-end models. It is used across the entire C7 generation of the Audi A7 and the sporty Audi RS7, spanning model years 2010 to 2018—including facelifted variants.

At Airbag24, we repair the 4G0959655A control unit for the following specific vehicle models:

Audi A7: C7 4G (model years 2010–2014) and C7 4G Facelift (model years 2014–2018)

Audi RS7: C7 4G (model years 2013–2014) and C7 4G Facelift (model years 2014–2018)

How is the 4G0959655A repaired?

Repair at Airbag24 follows a proven, professional process. After receiving the removed control unit, our technicians conduct a detailed fault analysis. Depending on the issue, they either erase crash data or repair defective electronic components. Each repair comes with 2 years' statutory liability for defects.

The first step involves carefully removing the control unit from the vehicle and securely shipping it to Airbag24.

Upon receipt, the 4G0959655A control unit is inspected using specialized diagnostic equipment to pinpoint the exact cause of the fault. With over 20 years of experience and more than 20,000 repairs completed, we ensure precise diagnosis.

Based on the analysis, restoration work is carried out, which may include professionally erasing crash data or replacing faulty electronic components on the circuit board.

After successful repair, the control unit undergoes a comprehensive functional test to confirm full operability. It is then returned to you, ready for immediate reinstallation.