Airbag control unit with part number 98820-4HD0B

What does the airbag control unit 98820-4HD0B do?

The airbag control unit 98820-4HD0B forms the central control unit of the SRS system of Infiniti. It evaluates the data from the crash sensors and, in the event of an accident, decides within milliseconds which airbags and seatbelt pretensioners fire.

During normal operation the unit checks the system continuously. If it detects a fault, the airbag warning light in the instrument cluster lights up.

After an accident the control unit secures crash data and then remains locked.

Why does the control unit 98820-4HD0B fail?

On the 98820-4HD0B, the most common cause lies in crash data stored after an accident, even if no airbag has triggered. Added to this are aged electronics, cold solder joints, moisture and corrosion on plugs, and voltage spikes.

An ordinary diagnostic tool cannot erase such crash data. Airbag24 removes it during the repair.

The other causes at a glance:

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

How can you tell that the 98820-4HD0B is defective?

Typical signs are an airbag warning light that lights up permanently or from time to time, and a fault message in the instrument cluster. On the 98820-4HD0B, a diagnostic tool without a connection to the control unit and a fault memory that cannot be cleared are further indications.

The signs in detail:

• Airbag warning light in the instrument cluster, permanently or from time to time
• Fault message in the instrument cluster
• Diagnostic tool has no connection to the control unit
• Fault memory cannot be cleared

In such a case airbags and seatbelt pretensioners may not trigger in an emergency. The warning light indicates the defect, so do not ignore it.

Which vehicles is the 98820-4HD0B fitted in?

The assignment concerns Infiniti. The control unit 98820-4HD0B is fitted in these vehicles: Infiniti Q50 V37 (2013-2024).

In detail, these are the vehicles:

• Infiniti Q50 V37 (2013-2024)

Comparing the part number on the label of the removed unit with this page only confirms that it is the right unit. Have the fault memory read out first, because 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 988206HE0A, K8820-4HL0A.

How does the repair of the 98820-4HD0B work?

During the repair of the 98820-4HD0B, first have the fault memory read out and enclose the log. Then disconnect the battery and remove the control unit. Create the repair order online and send in the unit, packed well.

Airbag24 checks the control unit on the test bench and replaces defective components. Stored crash data is erased, followed by a function test, and then your own unit goes back to you. Processing at Airbag24 usually takes 3–4 working days.

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 98820-4HD0B get to Airbag24?

You send the unit 98820-4HD0B in yourself as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends the control unit back to you by UPS.

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