Airbag control unit with part number 985105099R

What does the airbag control unit 985105099R do?

The airbag control unit 985105099R is the central control unit of the restraint system (SRS) at Renault. It evaluates the signals from the crash sensors, decides within milliseconds in an accident on the triggering of airbags and seatbelt pretensioners, and monitors the system constantly. It reports detected faults via the airbag warning light.

The electronics remain active during operation and check their connections.

An accident causes the unit to store crash data and lock itself.

Why does the control unit 985105099R fail?

The most common cause for the 985105099R is crash data from an earlier accident, even if no airbag fired. An ordinary diagnostic tool cannot erase it. In addition there are ageing, moisture at plug connectors, cold solder joints and voltage spikes.

Airbag24 removes the crash data itself, so you do not have to attend to it.

Ageing affects components over time, solder joints can become weak, and moisture has a corrosive effect on plug connectors.

A weak battery or a jump start generates voltage spikes that stress the electronics.

How can you tell that the 985105099R is defective?

A defect shows through the airbag warning light when it lights permanently or intermittently in the instrument cluster. A fault message in the instrument cluster, a missing connection to the diagnostic tool or a fault memory that cannot be erased also indicate a problem on the 985105099R.

As soon as the system detects a fault, the light shows it. As long as a problem exists, the indication stays active.

In an emergency, the airbags and seatbelt pretensioners may then not be able to fire. Arrange a check promptly.

Which vehicles is the 985105099R fitted in?

The airbag control unit 985105099R is fitted in these vehicles: Renault Mégane IV (from 2016).

Here is the overview:

• Renault Mégane IV (from 2016)

Check on the removed unit whether the part number on the label matches this page. This shows only whether it fits, nothing more. Have the fault memory read out beforehand, because only its findings show 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 985101957R, 985104870R, 985107896R, 985108011R.

How does the repair of the 985105099R work?

First read out the fault memory and attach the log to the unit. Then disconnect the battery, and only then remove the control unit. Create the repair order online, and then send the well-packed unit in.

At Airbag24 the unit is checked, defective components are replaced, stored crash data is erased and a function test is carried out. These steps usually take 3–4 working days 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. You then receive your unit back.

How does the control unit 985105099R get to Airbag24?

You send the control unit 985105099R to Airbag24 as a parcel or book a UPS collection for an extra charge. The return after the repair is made by UPS. The printed repair order goes into the parcel.

Pack the unit shockproof so that it arrives at Airbag24 undamaged.