Airbag control unit with part number 98221VC021

What does the airbag control unit 98221VC021 do?

The restraint technology (SRS) of Subaru is controlled by the airbag control unit 98221VC021. It evaluates the crash sensors, decides in a crash on the firing of airbags and seatbelt pretensioners and monitors the system continuously. It shows faults via the airbag warning light; after a crash it stores crash data and locks itself.

Monitoring takes place during operation, as the unit checks connections and components continuously.

The sensors are evaluated within the unit itself, and it reaches its decision in the shortest possible time.

Why does the control unit 98221VC021 fail?

The most common cause is stored crash data after an accident, even if no airbag has deployed. With this control unit, clearing the crash data is often not possible; if you want the data cleared, contact Airbag24 briefly before sending the unit in, and Airbag24 will then check the part number. Other causes are aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

After a crash the unit stores crash data, even when no airbag has deployed. This data is therefore at the top of the list when troubleshooting begins.

The other causes concern the electronics in the unit and its connections. Aged components and cold solder joints are as possible as moisture and corrosion at the plugs.

Voltage spikes, for example from a weak battery or a jump start, also count among the causes.

How can you tell that the 98221VC021 is defective?

The airbag warning light in the instrument cluster lights up constantly or intermittently, a fault message appears in the instrument cluster, the diagnostic tool makes no connection to the control unit, or the fault memory cannot be cleared. In an emergency the airbags and seatbelt pretensioners may then fail to deploy.

The warning light is a clear indication that the system is not working without fault. If it lights up, take it seriously.

A light that comes on only intermittently, as well as fault messages in the instrument cluster are also reasons to have the system checked.

Which vehicles is the 98221VC021 fitted in?

The airbag control unit 98221VC021 is fitted in these vehicles: Subaru WRX VB (from 2021); Subaru Levorg VN (from 2020). The list names the models known for this control unit.

The known vehicles are listed here:

• Subaru WRX VB (from 2021)
• Subaru Levorg VN (from 2020)

Comparing the part number on the label of the removed unit with this page only confirms that it is the right unit. Having the fault memory read out is the step that 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 98221VC030, 98221VC031, 98221VC200, 98221VC210.

How does the repair of the 98221VC021 work?

First have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit. Then create a repair order online and send the unit in. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 tests the unit on the test bench, replaces defective components and runs a function test. After that your own unit goes back to you.

If you want the crash data cleared, contact Airbag24 briefly before sending the unit in.

The sequence of steps serves safety. 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 98221VC021 get to Airbag24?

You send the unit to Airbag24 as a parcel, or you book a UPS collection for an extra charge. Airbag24 handles the return shipment by UPS.

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