Airbag control unit with part number 985105866R

What does the airbag control unit 985105866R do?

The airbag control unit 985105866R coordinates the restraint system (SRS) in the Renault. In an impact, it reads the measured values of the crash sensors and determines within a fraction of a second which airbags and seatbelt pretensioners fire.

During continuous operation, the electronics also monitor the components and the wiring of the system. If they find a fault, they show it via the airbag warning light in the instrument cluster.

If an accident occurs, the unit stores crash data in its memory and then locks itself. In addition, the supplier number Bosch 0285015296 is printed on the housing.

Why does the control unit 985105866R fail?

For the control unit 985105866R, stored crash data is the most common cause, even if no airbag has deployed. Further causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or a jump start.

A normal diagnostic tool cannot delete the crash data. Airbag24 removes it during the repair.

The other causes concern the electronics over time: components age, solder joints can go cold, and moisture or corrosion attack the plug contacts. Which of these applies in an individual case can only be shown by the inspection.

How can you tell that the 985105866R is defective?

The airbag warning light in the instrument cluster lights up on the 985105866R permanently or from time to time. In addition, there may be a fault message in the instrument cluster, the diagnostic tool may have no connection to the control unit, or the fault memory cannot be cleared.

The warning light is the clearest sign that the system has detected a fault. Whether it stays on constantly or only comes on occasionally, it deserves attention in every case.

In an emergency, airbags and seatbelt pretensioners may not be able to fire with such a fault. Therefore, an inspection is the right next step as soon as the light comes on.

Which vehicles is the 985105866R fitted in?

The 985105866R is fitted in these vehicles: Renault Arkana I (from 2019).

The affected vehicles are listed in the following overview.

• Renault Arkana I (from 2019)

First: compare the part number on the label of the removed unit with this page. This only confirms that you have the correct unit in front of you. Second: have the fault memory read out beforehand. Only this log shows whether the control unit itself is defective or whether a plug or a 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 985105866R work?

First, you have the fault memory read out and attach the log. Then you disconnect the battery, only then remove the control unit 985105866R, and create a repair order online.

Next, you send the well-packed unit in. Airbag24 checks it on the test bench, replaces defective components, deletes the stored crash data and carries out a function test.

Processing at Airbag24 usually takes 3–4 working days. Afterwards, your own, repaired unit is returned to you.

The sequence serves your safety, because the control unit may only be removed once the battery has been disconnected. 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 985105866R get to Airbag24?

You send the control unit 985105866R as a parcel, or you book a UPS collection for an extra charge. After the repair, Airbag24 sends it back to you by UPS.

Put the printed repair order into the parcel and pack the unit shock-proof.