Airbag control unit with part number 28556-3SR0A

What does the airbag control unit 28556-3SR0A do?

The airbag control unit 28556-3SR0A is the central control unit of the restraint system in Nissan. It processes the signals from the impact sensors, selects which airbags and seatbelt pretensioners to trigger within milliseconds of a crash, and monitors the system continuously.

The unit reports faults via the airbag warning light in the instrument cluster. The warning light is therefore the visible sign of the condition of the system.

After a crash, the control unit stores crash data and locks itself.

Why does the control unit 28556-3SR0A fail?

On the 28556-3SR0A, stored crash data after an accident is the most common cause, even if no airbag has deployed. This data cannot be erased with a normal diagnostic tool; Airbag24 deletes it during the repair. Other causes include aged electronics, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

After an accident, the unit can show faults even though little is visibly wrong on the vehicle.

The remaining causes lie in the electronics. Over time components age, solder joints can stay cold or lose contact, and moisture entering plug connectors leads to corrosion. Voltage spikes, for example from a weak battery or when jump-starting, also stress the electronics.

How can you tell that the 28556-3SR0A is defective?

A defect on the 28556-3SR0A shows through the airbag warning light in the instrument cluster, which stays on permanently or intermittently. In addition, a fault message appears in the instrument cluster, or the diagnostic tool gets no connection to the control unit. A fault memory that cannot be cleared is also a sign.

In an emergency, airbags and seatbelt pretensioners may then fail to trigger. A finding like this is therefore nothing to ignore and is worth checking.

Which vehicles is the 28556-3SR0A fitted in?

The control unit 28556-3SR0A is fitted in these Nissan vehicles: Nissan Sylphy B17 (from 2012). This information relates to the assignment of this part number.

The following vehicles are on record:

• Nissan Sylphy B17 (from 2012)

A label check against this page only confirms that the correct unit is present. The cause is shown by the fault memory, which you should have read out before removal.

How does the repair of the 28556-3SR0A work?

First, have the fault memory read out and enclose the log. Then disconnect the battery and remove the control unit. Next, create a repair order online and pack the unit carefully for dispatch. At Airbag24, checking, repairing and testing usually takes 3–4 working days.

The order of these steps protects you when working on the airbag system; removal only takes place after the battery has been disconnected.

At Airbag24, the unit is checked, defective components are replaced, and stored crash data is deleted. The function test follows, and your 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 28556-3SR0A get to Airbag24?

You send the 28556-3SR0A as a parcel or book a UPS collection for an extra charge. UPS handles the return journey, with which Airbag24 sends the repaired unit back.

Place the printed repair order in the parcel and pack the control unit shock-proof.