Airbag control unit with part number 98820-3AA0A

What does the airbag control unit 98820-3AA0A do?

The airbag control unit 98820-3AA0A is the central control unit of the restraint system (SRS) for Nissan. It evaluates the signals from the crash sensors, decides within milliseconds in an accident about triggering airbags and seatbelt pretensioners, and monitors the system constantly. After an accident it stores crash data and locks itself.

If the system detects a fault, it indicates it via the airbag warning light in the instrument cluster. The sensors supply measured values; the actual decision is made by the control unit.

The monitoring covers the sensors, the airbags, the seatbelt pretensioners and the supply voltage. In normal driving nothing of this is noticeable, because the system works in the background and responds in an accident.

Why does the control unit 98820-3AA0A fail?

The cause is most often to be found in stored crash data. They arise after an accident, even if no airbag was triggered, and an ordinary diagnostic tool does not remove them from the memory. Other possible causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or a jump start.

Stored data remain in the unit until they are deliberately removed. This applies regardless of how the vehicle continues to be driven afterwards.

Aged components and corrosion on contacts impair function over a longer period. Moisture in plug connections leads to transition resistances that become noticeable only gradually. Voltage spikes additionally stress the electronics.

How can you tell that the 98820-3AA0A is defective?

A defect first becomes noticeable at the airbag warning light in the instrument cluster, which lights up permanently or intermittently. Accompanying this, an error message appears in the instrument cluster, the diagnostic tool cannot find the control unit, and the fault memory cannot be erased.

Until the cause is clarified, airbags and seatbelt pretensioners may possibly fail to trigger in an emergency. The display therefore concerns the entire restraint system, not just one detail.

That an entry is stored says nothing yet about its severity. Only the readout makes the finding tangible, and the warning light is there precisely to make a defect visible.

Which vehicles is the 98820-3AA0A fitted in?

The 98820-3AA0A is fitted in these vehicles: Nissan Almera N17 (2011-2020).

The list below shows the individual vehicles in detail:

• Nissan Almera N17 (2011-2020)

Two steps help with the assignment. Compare the part number on the label of the removed unit with this page; then you know that it is the right unit. Have the fault memory read out beforehand, because only 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 28556-9KN1B, 98820-9KA0A.

How does the repair of the 98820-3AA0A work?

First have the fault memory read out and enclose the log. Only then disconnect the battery and remove the control unit. Next create a repair order online and send in the well-packed unit.

Airbag24 tests the unit on the test bench, repairs defective components, erases stored crash data and carries out a function test. After that your own unit is returned 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 98820-3AA0A get to Airbag24?

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

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