Airbag control unit with part number 98221AN01C

What does the airbag control unit 98221AN01C do?

The 98221AN01C is the airbag control unit of the restraint system (SRS) in Subaru. It continuously monitors the crash sensors and decides in the event of a crash, within milliseconds, which airbags and seatbelt pretensioners are triggered. It reports faults via the airbag warning light.

The unit works in the background as long as the vehicle has power. It processes measurements from several sensors and distinguishes between normal driving and an impact that requires triggering.

After an accident it stores crash data and locks itself. For fault-finding in the workshop, this is the point where one starts first.

Why does the control unit 98221AN01C fail?

Stored crash data from an earlier accident is the most common cause, even if no airbag was triggered, and a normal diagnostic tool cannot erase it. Other possible causes are aged electronic components, cold solder joints, moisture and corrosion at connectors, and voltage spikes, for example with a weak battery or a jump start.

The unit stores crash data even when no airbag has been triggered. The fact that an accident without triggering already leaves such data can be overlooked during removal.

The other causes concern ageing, contact and power supply. Electronics wear out, solder joints can go cold, and moisture corrodes connectors. A voltage spike arises, for example, when the battery is weak or a vehicle starts with a jump start.

How can you tell that the 98221AN01C is defective?

A defect shows up in the airbag warning light in the instrument cluster, which is on constantly or intermittently. Fault messages in the instrument cluster, no connection to the diagnostic tool and a fault memory that cannot be cleared are added. Then airbags and seatbelt pretensioners may possibly not trigger in an emergency.

Which of these signs appear depends on the fault. The most important are:

• Airbag warning light on constantly or intermittently
• Fault message in the instrument cluster
• Diagnostic tool receives no connection to the control unit
• Fault memory cannot be cleared

With this warning light, a prompt check is worthwhile.

Which vehicles is the 98221AN01C fitted in?

The 98221AN01C is fitted in these vehicles: Subaru Forester SK Facelift (from 2021) and SK (2018-2021). The part number remains decisive, not the vehicle type alone.

These vehicles are recorded in our assignment to the part number:

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

Two points are important before you send the unit in. First: compare the part number on the label of the removed unit with this page; this alone clarifies whether it is the right unit. Second: have the fault memory read out, because only this shows whether the control unit itself is defective or whether a connector or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 98221-SJ370, 98221AN00A, 98221AN00D, 98221AN00E, 98221AN01A, 98221AN01D.

How does the repair of the 98221AN01C work?

First have the fault memory read out and attach the log, then disconnect the battery and remove the control unit afterwards. Create the repair order online and send the unit in well packed. Airbag24 usually needs 3–4 working days for checking, repairing and testing.

At the test bench, Airbag24 examines the unit, replaces defective components, deletes stored crash data and carries out a function test. Then your own unit is returned to you.

This sequence protects you: only after the battery has been disconnected is the control unit removed.

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 98221AN01C get to Airbag24?

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

Put the printed repair order with it and pack the unit shockproof.