Airbag control unit with part number 654779

What is the function of Airbag Control Unit 654779?

The airbag control unit with part number 654779 is the central control module for the passive safety system in the Peugeot 106. It continuously monitors signals from crash sensors, processes them in real time, and ensures that airbags and seatbelt pretensioners are deployed precisely in the event of a collision.

As the “brain” of the restraint system, this component constantly collects data from various acceleration and G-force sensors throughout the vehicle. In the event of a crash, the control unit determines within milliseconds which safety devices need to be activated to provide optimal protection for occupants.

In addition, it communicates with the vehicle’s electrical system and reports the system status to the instrument cluster, where it is displayed via the airbag warning light. Therefore, proper functionality is essential for vehicle safety.

Why does control unit 654779 fail?

Malfunctions in control unit 654779 often arise from internal errors that prevent communication with diagnostic tools, or from blocked crash data—even without an actual accident. Other causes include electronic components that fail due to aging, moisture, or electrostatic discharge.

A primary cause is an internal memory error, where so‑called crash data becomes stuck in the EEPROM chip of the control unit. This condition locks the device’s normal operation and renders it unresponsive to diagnostic equipment.

Furthermore, hardware defects can also occur directly on the circuit board. Aging leads to failures in capacitors or microcontrollers, while ingress of moisture or improper handling (such as electrostatic discharge) may result in short circuits and other damage.

Similar technical issues also affect comparable control units, such as part numbers 9673605880 and 618294300, which share a similar design architecture.

How do you recognize a fault in Airbag Control Unit 654779?

The most obvious sign of a malfunction in control unit 654779 is a permanently illuminated airbag warning light on the instrument panel. Often, the control unit can no longer be read by diagnostic equipment—communication either fails entirely or results in the display of internal error codes.

The primary symptom is the persistently lit airbag warning lamp. Instead of extinguishing after starting the vehicle as intended, it remains on continuously, indicating a critical system failure.

Another clear indication is the inability to perform diagnostics. When a workshop attempts to read the fault memory, the diagnostic tool receives no response from the control unit, making it appear as though the unit is not installed in the vehicle at all.

If some communication still occurs, specific error codes such as “Internal Error” are frequently stored in the fault memory. These directly point to a defect within the control unit itself, rather than to problems with external sensors.

Even after an accident, when all visible components like airbags and seatbelt pretensioners have been replaced, the warning light remains active. The underlying cause is the locked crash data inside the control unit, preventing reactivation.

In which models is control unit 654779 installed?

The airbag control unit with part number 654779 is specifically designed for various model series of the Peugeot 106. At Airbag24, we professionally repair this control unit for both the first and second generations of this compact car, restoring full functionality to the safety system.

Repair services at Airbag24 are a proven solution for the first‑generation Peugeot 106 (S1), manufactured from 1991 to 1996.

Similarly, the component is expertly refurbished for the second generation of the Peugeot 106 (S2), produced between 1996 and 2003.

What are the benefits of repairing 654779?

Repairing the original airbag control unit 654779 offers significant cost savings compared to purchasing an expensive new part. Additionally, there’s no need for time‑consuming re‑programming or recalibration, as the repaired unit remains vehicle‑specific and ready for immediate use.

The financial advantage is substantial. While a new control unit from the manufacturer can easily cost up to 800 euros, repair represents a far more economical alternative without compromising safety or functionality.

Since the original component is retained and only undergoes electronic refurbishment, no complicated coding or programming work is required upon reinstallation. The control unit is plug-and-play.

Moreover, repair provides a sustainable solution, helping to reduce electronic waste and conserve existing resources. We offer a 12‑month warranty on every repair performed.

How is control unit 654779 professionally repaired?

At Airbag24, the repair of control unit 654779 begins with a precise electronic analysis of the circuit board. Defective components are replaced, and stored crash data is professionally erased. Following a comprehensive functional test, the unit is returned ready for installation, backed by a 12-month warranty.

Before removal, it is absolutely essential to disconnect the vehicle battery for at least 15 minutes to prevent residual voltage. Additionally, ESD protection measures—such as touching the vehicle body—should be taken to avoid damaging the sensitive electronics.

Upon arrival at Airbag24, specialized technicians open the housing and perform diagnostics directly on the circuit board. Defective components, including capacitors, resistors, or memory chips, are identified and replaced with new, high-quality parts.

A key step is resetting the stored crash data. Using specialized software, the control unit’s memory chip is read out, and any lock preventing further use is removed, restoring the data set to its factory‑original state.

Finally, the repaired control unit undergoes a complete functional test, ensuring flawless communication with diagnostic systems and proper processing of sensor signals. Each repair is completed with a 12-month warranty.

What shipping options does Airbag24 offer?

For sending your defective control unit, Airbag24 provides flexible and secure options. You can ship the package yourself free of charge or arrange a convenient UPS pickup. For return shipping, you have access to free standard UPS delivery, express options, and cash-on-delivery payment.

For outbound shipping, you have two choices: you can send the control unit yourself at no cost, or book the convenient UPS pickup service at a location of your choice.

The return shipment of the repaired unit is normally provided free of charge via standard UPS delivery, which typically takes 1–3 business days to arrive.

If faster delivery is needed, you can opt for UPS Express shipping, which ensures delivery within 1–2 business days.

Both standard and express shipping can optionally be combined with cash-on-delivery as the payment method. Alternatively, in‑person pickup at our facility is also available.