00655-001 airbag control unit fault

What does error code 00655-001 mean?

Error code 00655-001 indicates a fault in the airbag system, specifically related to the seatbelt pretensioner circuit. The cause is usually an incorrect resistance value in the pretensioner igniter, damaged wiring, or an internal hardware defect within the airbag control unit itself.

Technically, the airbag control unit continuously monitors the resistance of all ignition modules, including the seatbelt pretensioners. If the measured value deviates from the target values stored in the control unit—either too high or too low—the error code 00655-001 is set, and the airbag warning light illuminates.

This error code is safety‑critical, as the seatbelt pretensioner’s functionality may no longer be guaranteed in the event of a crash. The system switches to a safe mode to prevent false activations and permanently signals the fault.

How can you recognize error code 00655-001?

The primary symptom of error code 00655-001 is a constantly illuminated or flashing airbag warning light on the instrument panel. Although the fault can be read with a diagnostic tool, it usually cannot be cleared permanently, as it represents an active, safety‑relevant issue.

The airbag warning light clearly informs the driver that there is a malfunction in the restraint system. The light does not turn off after starting the vehicle and remains on throughout the drive.

Another clear indication is how the fault appears when reading the fault memory. Even if the error is cleared, it reappears immediately after another ignition cycle or system check.

At the latest during the next main inspection (HU), this error code will result in failure, since the airbag system must function flawlessly as a critical safety component.

What causes error code 00655-001?

The most common cause of error code 00655-001 is a defective seatbelt pretensioner igniter whose resistance falls outside the specified tolerance. Other reasons include cable breaks or corroded connectors leading to the pretensioner, as well as an internal hardware defect on the airbag control unit’s circuit board.

The seatbelt pretensioner igniter itself is often at the root of the problem. Due to aging or vibrations, the internal resistance of the igniter may change, which the control unit promptly detects and logs as a fault.

A very common cause is mechanical damage to the wiring. In particular, the connectors under the front seats or near the B‑pillar are prone to loose connections or cable breaks caused by seat adjustments and belt movements.

Rarer but still possible is a defect in the airbag control unit. Moisture, short circuits, or the aging of electronic components on the circuit board can lead to misinterpretation of the seatbelt pretensioner circuit’s measurements.

Which vehicles are affected by error code 00655-001?

Error code 00655-001 frequently occurs in certain Bentley models, especially the Azure and Continental. Similar issues in the seatbelt pretensioner system are also known in other brands such as Volkswagen, Audi, and Škoda, often under the basic error code 00655.

At Airbag24, we specialize in successfully repairing this error code for the following vehicles:

Bentley Azure 1st Generation (model years 2006–2011)

Bentley Continental T 1st Generation (model years 1991–2002)

Bentley Continental Supersports Mk1

How is error code 00655-001 professionally repaired?

Professional repair requires a detailed analysis after removing and sending in the airbag control unit. At Airbag24, depending on the cause, defective electronic components on the circuit board are replaced, or internal device data is reset. The unit is then thoroughly tested and fully functional again.

The repair process begins with the proper removal of the airbag control unit from the vehicle. After secure packaging, the unit is shipped to the Airbag24 workshop.

There, technicians perform an incoming inspection to verify the reported fault. The control unit is then opened, and the circuit board is analyzed at the hardware level. Defective components such as resistors, capacitors, or processors are identified and replaced with new, high‑quality parts.

Once the repair work is complete, the control unit undergoes a comprehensive functional test. If successful, it is prepared for return shipment and can be installed without further programming. We provide 2 years' statutory liability for defects on all repairs performed.

Is it worth repairing error code 00655-001?

Repairing the airbag control unit for error code 00655-001 is an economically and technically sensible alternative to the costly purchase of a new unit. It delivers substantial cost savings of up to 90 percent compared to the price of a new part, which often runs into several hundred euros.

According to the manufacturer, buying a new airbag control unit can cost as much as 750 euros. In contrast, repair offers a significantly more budget-friendly solution without compromising safety or functionality.

An additional key advantage is that the repaired original control unit retains its vehicle-specific coding. This eliminates the need for time-consuming reprogramming, which would be required when installing a new unit at an authorized service center. Once installed, the repaired unit works immediately—plug-and-play.

With 2 years’ statutory liability for defects on the work performed, the repair also provides a secure and reliable solution to restore full functionality to the airbag system.