Airbag control unit with part number 98221SJ270

What does the airbag control unit 98221SJ270 do?

The airbag control unit 98221SJ270 is the control unit of the SRS restraint system in Subaru. It processes the signals from the crash sensors and, in a crash, decides within milliseconds which airbags and seatbelt pretensioners are triggered. It also monitors the entire system and reports faults via the airbag warning light.

This monitoring runs in the background. Every detected fault is recorded in the fault memory.

After a crash, the unit stores crash data and locks itself. The next section explains what this means for the repair.

Why does the control unit 98221SJ270 fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed. A normal diagnostic tool cannot delete this data. Aged components, cold solder joints, moisture and corrosion, and voltage spikes are also possible causes.

Airbag24 deletes the crash data during the repair.

• aged electronic components
• cold solder joints
• moisture and corrosion at plug connections
• voltage spikes, for example with a weak battery or a jump start

How can you tell that the 98221SJ270 is defective?

A defect shows up as the airbag warning light staying on permanently or intermittently, as a fault message in the instrument cluster, as a lack of contact between the diagnostic tool and the control unit, or as a fault memory that cannot be cleared. In this case, airbags and seatbelt pretensioners may fail to trigger in an emergency.

Typical signs at a glance:

• Airbag warning light permanently on
• Airbag warning light on intermittently
• Fault message in the instrument cluster
• Diagnostic tool receives no connection
• Fault memory cannot be cleared

The light shows the finding immediately.

Which vehicles is the 98221SJ270 fitted in?

The part number determines which models are affected. The 98221SJ270 is fitted in these vehicles: Subaru Forester SK (2018-2021) and SK Facelift (from 2021).

This list shows the models that Subaru specifies for the unit.

• 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 beforehand. This only shows that it is the correct unit. Also have the fault memory read out, because this result shows whether the control unit itself 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 98221SJ270 work?

You first have the fault memory read out and enclose the log; then disconnect the battery and remove the control unit. Next, create a repair order online and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, deletes the stored crash data and carries out a function test. Afterwards, your own unit is returned 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 98221SJ270 get to Airbag24?

You send the unit in as a parcel or book a UPS collection for an extra charge. Airbag24 returns it by UPS after the repair.

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