Airbag control unit with part number 98820-4DH1B

What does the airbag control unit 98820-4DH1B do?

The airbag control unit 98820-4DH1B is the central control unit of the restraint system (SRS) of Nissan. It evaluates the signals from the crash sensors and, in an emergency, decides which airbags and seatbelt pretensioners are triggered.

The system is monitored continuously by the unit, which reports faults via the airbag warning light in the instrument cluster. After an accident it stores crash data and locks itself; the lock is lifted only by the repair.

During driving, the control unit works unobtrusively in the background.

Why does the control unit 98820-4DH1B fail?

With the 98820-4DH1B, the most common cause is crash data stored after an accident, even if no airbag has deployed. Alongside this, aged electronic components and cold solder joints are involved, as are moisture and corrosion at plug connectors.

Crash data cannot be erased with an ordinary diagnostic tool; Airbag24 takes care of this as part of the repair.

Voltage spikes, for example from a weak battery or from a jump start, are a further cause. The electronics can be damaged as a result.

How can you tell that the 98820-4DH1B is defective?

A fault on the 98820-4DH1B shows up through the airbag warning light in the instrument cluster, through an error message in the same display, through a lack of contact with the diagnostic tool, or through a fault memory that cannot be cleared.

The light may stay on permanently or only come on intermittently, and in both cases the display is a signal of a fault. A fault memory that cannot be cleared confirms this additionally.

In an emergency, airbags and seatbelt pretensioners may then fail to trigger. Therefore arrange a check promptly.

Which vehicles is the 98820-4DH1B fitted in?

The airbag control unit 98820-4DH1B is fitted in these vehicles: Nissan Maxima A36 (2015-2023).

These vehicles are known for this part number:

• Nissan Maxima A36 (2015-2023)

Compare the number on the label of the removed control unit with this page. This shows that you have the correct unit; the comparison says nothing more. Have the fault memory read out beforehand, because only the log shows whether the control unit itself is the cause or whether a plug or a cable is behind it.

For the same vehicles, we also repair control units with the part numbers 98820-3Y600, 98820-AV200, 98820-AV21A.

How does the repair of the 98820-4DH1B work?

Processing the 98820-4DH1B at Airbag24 usually takes 3–4 working days. This time covers only the checking, repairing and testing in our own workshop.

Beforehand the fault memory is read out and the log is enclosed, then the battery is disconnected. Only then do you remove the control unit and create the repair order online.

Airbag24 checks the unit on the test bench, replaces defective components, erases the 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 98820-4DH1B get to Airbag24?

You can send the 98820-4DH1B in as a parcel or have it collected by UPS for an extra charge. After the repair, Airbag24 returns your own unit by UPS.

The printed repair order goes into the parcel; the unit should be packed shock-resistant.