Airbag control unit with part number 98820-4BF0A

What does the airbag control unit 98820-4BF0A do?

The airbag control unit 98820-4BF0A is the central control unit of the restraint system (SRS) of Nissan. It evaluates the crash sensors, decides in a crash within milliseconds which airbags and seatbelt pretensioners to trigger, and monitors the system continuously.

The check runs in the background while the vehicle is being driven. If the unit detects a fault, it reports it via the airbag warning light in the instrument cluster and creates an entry in the fault memory. In this way, you notice a fault without a workshop first having to search for it.

After an accident, the control unit stores crash data and then locks itself. You will find more about this data and its consequences in the next section.

Why does the control unit 98820-4BF0A fail?

Most often this is due to crash data stored after an accident, even if no airbag has deployed. A normal diagnostic tool cannot remove this data. Other possible causes are aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

The crash data remains in the memory of the unit, even if nothing conspicuous can be seen on the outside of the vehicle. That is why it is always worth checking this memory before testing parts when a failure occurs.

The other causes can be everyday stresses on the electronics. These include in particular:

• aged electronic components on the circuit board
• cold solder joints that come loose under vibration
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery or a jump start

How can you tell that the 98820-4BF0A is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. In addition, an error message appears in the instrument cluster, the diagnostic tool gets no connection to the control unit, and the fault memory cannot be cleared.

So the warning light shows the defect by itself, and no test is needed to detect it. In an emergency, the airbags and seatbelt pretensioners may then fail to deploy. If the light stays on permanently, have the system checked before you continue driving.

Which vehicles is the 98820-4BF0A fitted in?

The control unit 98820-4BF0A is fitted in these vehicles: Nissan X-Trail T32 (2014-2017) and T32 Facelift (2017-2022).

The assignment is based on our data for this part number and serves as a first guide. The vehicles at a glance:

• Nissan X-Trail T32 (2014-2017)
• Nissan X-Trail T32 Facelift (2017-2022)

Compare the part number on the label of the removed unit with this page. This only confirms that it is the right unit, nothing more. Have the fault memory read out first, because only the result shows whether the control unit itself is defective or whether a plug or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 28556-4CG0A, 28556-4CH0A, 28556-4CJ0A, 28556-4CM0A, 28556-4CS0A, 98820-4CG0A.

How does the repair of the 98820-4BF0A work?

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

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. Your own, repaired unit is then returned to you. For testing, repairing and checking at Airbag24, 3–4 working days are usually scheduled.

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 98820-4BF0A get to Airbag24?

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

Put the printed repair order into the parcel and pack the unit shockproof before it goes on its way. That way it arrives safely at Airbag24.