Airbag control unit with part number 550735100

What does the airbag control unit 550735100 do?

The airbag control unit 550735100 coordinates the SRS restraint system in Renault. It reads the signals from the crash sensors, works out within milliseconds whether airbags and seatbelt pretensioners must trigger, and monitors the system without interruption. After an accident it stores crash data and locks itself.

This monitoring runs in the background. As soon as a component or a line shows irregularities, the unit reports it via the airbag warning light in the instrument cluster.

Anyone holding the part number 550735100 has the central unit of the system in hand, not merely a component at the periphery.

Why does the control unit 550735100 fail?

The most common reason is crash data stored in the memory after an accident, without an airbag having had to trigger; a conventional diagnostic tool does not make them disappear. Ageing electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes can likewise cause the failure. Airbag24 deletes the crash data during the repair.

Crash data document the load that the unit evaluated as an accident. Whether a seatbelt pretensioner or an airbag was involved plays no role for the memory.

The second group of causes concerns the components themselves. Over the years electronic parts can age, and solder joints on the circuit board can lose contact.

The third group is the environment and the on-board electrical system. Wetness and corrosion at connectors, as well as voltage spikes, for example from a weak battery or jump starting, belong to it.

How can you tell that the 550735100 is defective?

The airbag warning light in the instrument cluster stays on permanently or flickers intermittently, and a fault message appears in the instrument cluster. In addition, the diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared. In an emergency, airbags and seatbelt pretensioners may possibly not trigger.

The warning light shows the defect instead of hiding it. That is why it is worth taking every warning in the instrument cluster seriously, because it comes from the unit itself. If you notice a permanent or recurring display, have the vehicle checked promptly. Only the diagnosis clarifies whether the control unit itself is affected or whether a cable is the cause.

Which vehicles is the 550735100 fitted in?

The part number 550735100 is fitted in these vehicles: Renault Espace III (1996-2002). The assignment is based on the number on the unit, not on the model name.

Below follows the list of vehicles on record for this number.

• Renault Espace III (1996-2002)

Two things help before removal. Comparing the label number with this page only ensures that you remove the correct unit. Reading out the fault memory, on the other hand, shows whether the control unit is defective or whether a plug or cable is the cause, and that is what brings clarity.

For the same vehicles, we also repair control units with the part numbers 550346000, 6025308852F, 6025313596F, 6025371287.

How does the repair of the 550735100 work?

The process begins with reading out the fault memory, whose log you enclose, and with disconnecting the battery. Only then do you remove the control unit, create a repair order online and send it in well packed. At Airbag24 it is checked, repaired, cleared of crash data and tested; as a rule, 3–4 working days are to be expected for this.

The sequence is part of the safety requirements. Removal begins only once the battery is disconnected.

Afterwards your own unit makes its way back. The 3–4 working days refer only to the work at Airbag24.

Our repairs come with 2 years' statutory liability for defects.

The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.

How does the control unit 550735100 get to Airbag24?

The unit reaches Airbag24 as a parcel that you send yourself, or by a UPS collection booked for an extra charge. UPS also handles the return journey as soon as the repair is complete.

A printed repair order belongs in the parcel, and the packaging should protect the unit against shocks.