00655-002 airbag control unit fault

What does error code 00655-002 mean?

Error code 00655-002 indicates a specific issue with the passenger-side seatbelt pretensioner igniter, which carries the technical identifier N154. The airbag control unit has detected an electrical fault in this component’s circuit, suggesting a defective igniter, faulty wiring, or a poor connector.

Technically speaking, the airbag control unit continuously monitors the resistance of all safety‑related components. Code 00655-002 is triggered when the measured resistance value for igniter N154 falls outside the manufacturer‑defined tolerance range. This could indicate either excessively high resistance (open circuit) or excessively low resistance (short circuit).

In the event of a crash, the functionality of the passenger‑side seatbelt pretensioner may no longer be guaranteed due to this fault. For safety reasons, the system deactivates parts of the restraint system and alerts the driver to the critical condition by illuminating the airbag warning light.

How can you recognize error code 00655-002?

The primary symptom of error code 00655-002 is the persistent illumination of the airbag warning light on the instrument cluster. After starting the vehicle, the light fails to extinguish as usual and remains on, indicating a malfunction in the safety system. Typically, no additional driving‑related issues arise.

When reading the fault memory with an appropriate diagnostic tool, error code 00655-002 is clearly displayed alongside the description “Seatbelt Pretensioner Igniter (Passenger Side) – N154.” This enables targeted troubleshooting of the affected component.

A vehicle with an active airbag warning light will not pass its main inspection (TÜV), as the safety system is deemed non‑functional. Therefore, rectifying this fault is essential for road safety and compliance with legal regulations.

What causes error code 00655-002?

The most common cause of error code 00655-002 is a defect in the peripheral circuitry of the airbag control unit. Poor connector contacts—often located beneath the passenger seat—are the leading culprit, followed by a failure of the igniter itself or damaged cables. Less frequently, commissioning errors or diagnostic firewalls are responsible.

A very common source of trouble is the connector under the passenger seat. Over time, seat adjustments or vibrations can loosen or corrode the contact, resulting in an incorrect resistance reading in the circuit.

The seatbelt pretensioner igniter (N154) may also fail internally. A broken cable or damage to the wiring between the control unit and the pretensioner is another potential cause, which must be verified through visual and continuity checks.

In newer vehicles from model year 2019 onward, a so‑called diagnostic firewall may block write access required for reconfiguring the system’s default settings. This can mistakenly be interpreted as a component failure but is often resolved by opening the hood during the diagnostic procedure.

On which vehicles does error code 00655-002 occur?

Error code 00655-002 is primarily found in certain Bentley models from the VAG group. Older generations of luxury models that utilized this specific system configuration are particularly affected.

At Airbag24, we have experience diagnosing and repairing error code 00655-002 for the following specific models:

Bentley Azure Generation 1 (2006–2011)

Bentley Continental T Generation 1 (1991–2002)

Bentley Continental Supersports Mk1

How is error code 00655-002 professionally repaired?

Professional repair begins with a systematic diagnosis to isolate the exact cause. First, connectors and cables are inspected. Next, the igniter itself is tested. If necessary, the airbag control unit is re‑synchronized to restore full functionality.

The initial step in the workshop always involves visually inspecting the relevant components. Particular attention is paid to the connector under the passenger seat. It is disconnected, cleaned with contact spray, and checked for secure seating. Often, the problem is already resolved at this stage.

If cleaning the connector proves unsuccessful, the wiring between the control unit and the seatbelt pretensioner is examined for continuity and signs of damage. If the wiring is intact, this points to a defect in the igniter itself, which then requires replacement.

Following component replacement or wiring repairs, the system often needs to be re‑synchronized via a basic reset. Afterwards, the fault memory is cleared, and a final system check is performed to ensure the airbag warning light remains off permanently. We provide a 12‑month warranty on all repairs.

Is Repair Worth It for Error Code 00655-002?

Yes, targeted repair of the root cause is almost always the most cost-effective solution. Rather than replacing expensive components such as the entire airbag control unit outright, only the specifically defective parts are repaired or replaced. This results in substantial cost savings.

The cost of repairing the underlying issue—such as fixing a connector—is minimal compared to the price of a new airbag control unit, which can cost up to 750 euros. Specialized repair typically delivers savings of over 90%.

A professional repair restores the full functionality of the safety system and ensures that your vehicle will pass the next mandatory inspection. With a 12-month warranty on the work performed, this repair offers a safe and reliable alternative to an expensive new part.