Airbag control unit with part number 98221SJ310

What does the airbag control unit 98221SJ310 do?

The airbag control unit 98221SJ310 coordinates the restraint system (SRS) at Subaru. It reads the values of the impact sensors and, in an emergency, decides within fractions of a second which airbags and seatbelt pretensioners are triggered. After an accident it stores crash data and then locks itself.

The unit monitors the sensors, the wiring and the firing circuits of the airbags and seatbelt pretensioners continuously. If it finds a deviation, it creates a fault entry and shows the fault via the airbag warning light in the instrument cluster.

The actual evaluation takes place inside the unit. For the driver, a problem can therefore become visible only when the instrument cluster reacts.

Why does the control unit 98221SJ310 fail?

Stored crash data is the most common cause, even if no airbag was triggered in the accident; a normal diagnostic tool cannot erase it. Aged electronic components, moisture and corrosion at plug connections, and voltage spikes are also possible causes.

The crash data sits in the unit's memory. Airbag24 erases it during the repair, so no entry from the accident remains in the unit afterwards.

The other causes can act unnoticed over a long period. Cold solder joints on the circuit board and voltage spikes, for example from a weak battery or a jump start, can also affect the electronics.

How can you tell that the 98221SJ310 is defective?

A defect may show itself through the airbag warning light in the instrument cluster, which lights up permanently or intermittently, and through an error message there. The diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

• The airbag warning light lights up permanently or only intermittently.
• An error message appears in the instrument cluster.
• The diagnostic tool cannot establish a connection to the control unit.
• The fault memory cannot be cleared.

The warning light makes the defect visible. Therefore have the system checked promptly and do not wait for the light to go out on its own.

Which vehicles is the 98221SJ310 fitted in?

At Subaru, the airbag control unit 98221SJ310 is fitted in these vehicles: Subaru Forester SK (2018-2021) and SK Facelift (from 2021).

The following list shows the vehicles that Airbag24 has assigned so far.

• 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; this way you make sure it is the right unit. Also have the fault memory read out before you remove anything: only this log 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 98221SJ310 work?

First you read out the fault memory and enclose the log in the parcel. Then disconnect the battery and only afterwards remove the control unit 98221SJ310. Next, create a repair order online and send the well-packed unit in.

Airbag24 checks the unit on the test bench, replaces defective components and erases the stored crash data. A function test completes the work, after which your own unit is sent back to you.

Processing at Airbag24 usually takes 3–4 working days; this refers only to checking, repairing and testing. 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 98221SJ310 get to Airbag24?

You send the control unit 98221SJ310 to us as a parcel or book a UPS collection for an extra charge. After the repair, UPS brings your own unit back to you.

Put the printed repair order into the parcel and pack the unit shock-proof.