Airbag control unit with part number 550540000

What does the airbag control unit 550540000 do?

The central control centre of the restraint system in Fiat vehicles is the airbag control unit 550540000. It receives the signals of the crash sensors, determines in a fraction of a second in an accident which airbags and seatbelt pretensioners fire, and checks the system without interruption. It reports detected faults via the airbag warning light.

After an accident, it stores crash data and locks itself.

Why does the control unit 550540000 fail?

The most common cause is crash data stored after an accident, even without a triggered airbag. A normal diagnostic tool cannot erase this data. Further causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Airbag24 carries out the erasure as part of the repair. Aged components and cold solder joints can only be narrowed down within the unit itself.

Voltage spikes occur, for example, when the battery is weak or when jump-starting is used.

How can you tell that the 550540000 is defective?

The airbag warning light in the instrument cluster lights up constantly or at times. The instrument cluster also shows a fault message. In addition, the diagnostic tool gets no connection to the control unit, and the fault memory cannot be cleared.

Airbags and seatbelt pretensioners may then not deploy in an emergency. Have the system checked promptly.

Which vehicles is the 550540000 fitted in?

The control unit 550540000 is fitted in these vehicles: Fiat Scudo 220 (1996-2006); Fiat Ulysse 220 (1994-2000) and 220 Facelift (2000-2002).

The following list shows the vehicles in which this part number is fitted.

• Fiat Scudo 220 (1996-2006)
• Fiat Ulysse 220 (1994-2000)
• Fiat Ulysse 220 Facelift (2000-2002)

Compare the part number on the label of the unit with this page; this only confirms that you have the right unit. Have the fault memory read out beforehand, because only the log shows whether the control unit is defective or a connector or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 1480105080, 1480999080, 1486142080, 1496611080, 550539700, 550777700.

How does the repair of the 550540000 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit 550540000. Then create a repair order online and send the unit off well packed.

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. Processing at Airbag24 usually takes 3–4 working days.

You then receive your own unit back. 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 550540000 get to Airbag24?

Either you send the unit as a parcel, or you book a UPS collection for an extra charge. After the repair Airbag24 sends the unit back by UPS.

The printed repair order goes in the parcel, and the unit is packed shockproof.