Airbag control unit with part number 28556 BN903R

What does the airbag control unit 28556 BN903R do?

For Nissan, the airbag control unit 28556 BN903R controls the restraint system (SRS). From the signals of the crash sensors it determines whether, and which, airbags and seatbelt pretensioners are to be triggered in a crash. After an accident the unit stores crash data and locks itself.

It continuously checks itself and the system. A fault it finds appears via the airbag warning light in the instrument cluster.

This self-monitoring ensures that faults become visible to the driver.

Why does the control unit 28556 BN903R fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed; a normal diagnostic tool cannot erase it. For this control unit, erasing the crash data is often not possible; if you would like the data erased, contact Airbag24 briefly before sending the unit in, and Airbag24 will check the part number. Other causes to consider are ageing components, cold solder joints, corrosion at plug connectors, moisture and voltage spikes.

• ageing electronic components
• cold solder joints
• moisture and corrosion at plug connectors
• voltage spikes, for example from jump starting or a weak battery

Only the examination of the unit shows whether one of these causes is present.

Because of the crash data, it is worth a short consultation before sending the unit in, so that the part number can be checked.

How can you tell that the 28556 BN903R is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, and a fault message appears in the instrument cluster. The diagnostic tool cannot connect to the control unit, or the fault memory cannot be cleared.

• airbag warning light staying on or flashing
• fault message in the instrument cluster
• no connection between the diagnostic tool and the control unit
• fault memory that cannot be cleared

With such a finding, airbags and seatbelt pretensioners may not be able to trigger in an emergency. Take the warning seriously.

Which vehicles is the 28556 BN903R fitted in?

The 28556 BN903R is fitted in these vehicles: Nissan Almera N16 Facelift (2002-2006) and N16 (2000-2002).

You can see the individual vehicles in this list:

• Nissan Almera N16 Facelift (2002-2006)
• Nissan Almera N16 (2000-2002)

Compare the part number on the label of the removed unit with this page; that only ensures you have the right unit. Also have the fault memory read out beforehand, because only this log shows whether the control unit is itself defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 285001316, 285001318, 285001319, 285001638, 28556 5M303, 28556-BN903.

How does the repair of the 28556 BN903R work?

First have the fault memory read out and attach the log, then disconnect the battery and only then remove the control unit. Then create a repair order online and send in the well-packed unit. Airbag24 checks the unit on the test bench, repairs defective components and carries out a function test; processing usually takes 3–4 working days.

If you want the crash data erased, contact Airbag24 briefly before sending the unit in.

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 BN903R get to Airbag24?

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

Enclose the printed repair order in the parcel, and pack the unit shock-resistant.