Airbag control unit with part number 285556781R

What does the airbag control unit 285556781R do?

The airbag control unit 285556781R controls the restraint system (SRS) in the Renault. It processes the signals from the crash sensors, decides within milliseconds whether airbags and seatbelt pretensioners are triggered, and monitors the system continuously. After a crash, it stores crash data and locks itself.

If the unit detects a fault, it creates an entry in the fault memory and shows the fault via the airbag warning light in the instrument cluster.

Seatbelt pretensioners belong to the same system. In a crash they pull the belt tight, and the control unit triggers them together with the airbags.

Why does the control unit 285556781R fail?

The most common cause is stored crash data after an accident, even if no airbag has deployed; a normal diagnostic tool cannot erase it. Other possible causes are:

• aged electronic components
• cold solder joints
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery or jump-starting

An undamaged airbag does not mean that the control unit is untouched. The crash data remains stored in the unit, regardless of how the accident turned out.

How can you tell that the 285556781R is defective?

The airbag warning light in the instrument cluster lights up at times or constantly, and an error message also appears in the instrument cluster. In addition, the diagnostic tool cannot establish a connection to the control unit, and the fault memory cannot be erased. Airbags and seatbelt pretensioners may then possibly fail to trigger in an emergency.

The warning light is one of the most important warning signals of the system, because it shows the finding directly in the vehicle. A connection fault to the diagnostic tool, by contrast, does not necessarily originate in the control unit.

Which vehicles is the 285556781R fitted in?

The control unit 285556781R is fitted in these vehicles: Renault Arkana I (from 2019).

Here follows the list of the vehicles assigned to this part number:

• Renault Arkana I (from 2019)

Comparing the part number on the label of the removed unit with this page only confirms that it is the correct unit. Have the fault memory read out beforehand, because only it shows whether the control unit is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 285015832, 285A40674R, 285A49105R, 5D3EEF4828, 985103085R.

How does the repair of the 285556781R work?

First have the fault memory read out and attach the log. Then disconnect the battery, and only after that remove the control unit. Next, create a repair order online and send the unit in well packed. Airbag24 needs 3–4 working days as a rule for inspection, repair and testing.

At Airbag24, the unit is examined on the test bench, defective components are repaired, and stored crash data is erased. A function test follows before the unit goes back to you.

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 285556781R get to Airbag24?

You send the unit yourself as a parcel, or book a UPS collection for an extra charge. The return journey after the repair is made by UPS, once the repair is complete.

Put the printed repair order into the parcel and pack the control unit so that it withstands knocks.