Airbag control unit with part number 98221SJ300

What does the airbag control unit 98221SJ300 do?

The control unit 98221SJ300 is the airbag control unit of the restraint system (SRS) for Subaru. It processes the measurement data from the crash sensors, determines within fractions of a second in an impact whether airbags and seatbelt pretensioners are triggered, and checks the system permanently.

If the control unit detects a fault, it keeps the finding in memory and shows it via the airbag warning light.

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

Why does the control unit 98221SJ300 fail?

With the 98221SJ300, the most common cause after an accident is stored crash data, even without a triggered airbag. Added to this are ageing components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

An ordinary diagnostic tool cannot erase the crash data, so the problem remains even after reading out.

The other causes concern the electronics themselves. Components age, solder joints can go cold, and moisture or corrosion impair the contacts. Voltage spikes, for example with a weak battery or after a jump start, additionally stress the circuit.

Airbag24 erases the crash data during the repair. Which of the other causes is present is shown by the check.

How can you tell that the 98221SJ300 is defective?

A defect in the 98221SJ300 shows itself through the airbag warning light in the instrument cluster, which stays on permanently or intermittently. In addition, fault messages appear in the instrument cluster, the diagnostic tool finds no contact with the control unit, or the fault memory cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then fail to trigger.

The light indicates a defect and cannot be dismissed at a glance; the system must therefore be checked promptly.

Which fault is behind it becomes clear only from reading out the fault memory together with the check.

Which vehicles is the 98221SJ300 fitted in?

The control unit 98221SJ300 is fitted in these vehicles: Subaru Forester SK (2018-2021) and SK Facelift (from 2021).

The vehicles assigned to this part number are shown in this overview.

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

Compare the part number on the label of the removed unit with this page; that tells you that you have the right unit. Have the fault memory read out beforehand, because only this result shows whether the control unit itself is defective or 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 98221SJ300 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit 98221SJ300. Afterwards create a repair order online and send the unit in well packed.

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. Processing at Airbag24 usually takes 3–4 working days, and this time relates exclusively to this work.

Afterwards your own 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 98221SJ300 get to Airbag24?

You send the control unit 98221SJ300 as a parcel, or you arrange a UPS collection for an extra charge. After the repair, Airbag24 sends it back to you by UPS.

Enclose the printed repair order in the parcel and pack the unit shock-resistant.