Airbag control unit with part number 28556-4KJ0B

What does the airbag control unit 28556-4KJ0B do?

The airbag control unit 28556-4KJ0B controls the restraint system (SRS) for Nissan. It processes the signals from the crash sensors, decides in the event of an accident which airbags and seatbelt pretensioners are triggered, and monitors the system permanently.

The control unit reports faults via the airbag warning light in the instrument cluster. Faults are also recorded in the fault memory.

After an accident it stores crash data and locks itself. The unit is therefore a central component of the vehicle's safety technology.

Why does the control unit 28556-4KJ0B fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed. A standard diagnostic tool cannot erase it, so the fault persists.

Other causes include:

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

Which of these causes applies to your unit is only shown by the test on the test bench.

How can you tell that the 28556-4KJ0B is defective?

Typical signs are an airbag warning light in the instrument cluster that lights up permanently or intermittently, an error message in the instrument cluster, and a diagnostic tool without a connection to the control unit. The fault memory then cannot be cleared.

The signs include:

• the airbag warning light in the instrument cluster, permanently or intermittently
• an error message in the instrument cluster
• no connection to the diagnostic tool
• a fault memory that cannot be cleared

In an emergency, airbags and seatbelt pretensioners may not deploy. You should therefore have the fault clarified promptly.

Which vehicles is the 28556-4KJ0B fitted in?

The control unit 28556-4KJ0B is fitted in these vehicles: Nissan Frontier D23 (2015-2020); Nissan Navara D23 (2015-2020).

Here is an overview of the vehicles:

• Nissan Frontier D23 (2015-2020)
• Nissan Navara D23 (2015-2020)

Read out the fault memory before removal. This ensures that the control unit itself is defective and not a connector or a cable. Then compare the part number on the label with the information on this page.

For the same vehicles, we also repair control units with the part numbers 0 285 015 304, 28556-8Z325, 285569Z510, 28556EA10A, 98820 6KB0A, 98820 EB01D.

How does the repair of the 28556-4KJ0B work?

Processing at Airbag24 usually takes 3–4 working days. Before that, you read out the fault memory, remove the control unit and send it in with a repair order created online.

Enclose the log of the fault memory with the parcel. Disconnect the battery, remove the control unit 28556-4KJ0B and pack it well.

Airbag24 checks the unit, replaces defective components, erases stored crash data and carries out a function test. The own unit is then 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 28556-4KJ0B 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 by UPS.

The printed repair order belongs in the parcel. Pack the control unit 28556-4KJ0B shock-resistant.