Airbag control unit with part number 98221SJ390

What does the airbag control unit 98221SJ390 do?

In the Subaru, the airbag control unit 98221SJ390 coordinates the restraint system (SRS). In a crash it decides which airbags and seatbelt pretensioners are triggered, relying on the crash sensors.

During operation, the unit checks the system. It signals a malfunction via the airbag warning light in the instrument cluster.

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

Why does the control unit 98221SJ390 fail?

Stored crash data is the most common cause with the control unit 98221SJ390, even when no airbag has deployed. Other causes include aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes from a weak battery or jump-starting.

A normal diagnostic tool cannot erase the crash data. Airbag24 erases it as part of the repair.

The other causes are part of everyday electronics: components age, solder joints can go cold, and wetness with corrosion attacks the contacts. Voltage spikes place additional strain on the circuitry.

How can you tell that the 98221SJ390 is defective?

The airbag warning light in the instrument cluster lights up on the 98221SJ390 permanently or intermittently. In addition there may be a fault message in the instrument cluster, a diagnostic tool without connection, and a fault memory that cannot be cleared.

The warning light in particular is a clear signal that something is wrong in the restraint system. It cannot be ignored, even if the vehicle otherwise drives normally.

In an emergency, airbags and seatbelt pretensioners may fail to deploy in the event of a malfunction. A prompt check is therefore advisable.

Which vehicles is the 98221SJ390 fitted in?

The 98221SJ390 is fitted in these vehicles: Subaru Forester SK (2018-2021) and SK Facelift (from 2021).

The matching vehicles are listed below.

• Subaru Forester SK (2018-2021)
• Subaru Forester SK Facelift (from 2021)

First: compare the part number on the label of the removed unit with this page, so you know it is the correct unit. Second: read out the fault memory beforehand. Only the log 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 1523004370, 98221FC210, 98221SJ000, 98221SJ001.

How does the repair of the 98221SJ390 work?

First, have the fault memory read out and attach the log. Then disconnect the battery, remove the control unit 98221SJ390 and create your repair order online.

Then pack the unit well and send it in. Airbag24 tests it on the test bench, replaces defective components, erases the crash data and carries out a function test.

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

The order is prescribed for safety reasons. 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 98221SJ390 get to Airbag24?

You send the control unit 98221SJ390 in as a parcel or book UPS collection for an extra charge. Airbag24 sends the unit back to you by UPS after the repair.

Put the printed repair order in the parcel. The unit is packed shockproof.