Airbag control unit with part number 28556-3SV0A

What does the airbag control unit 28556-3SV0A do?

In the Nissan, the airbag control unit 28556-3SV0A takes over the control of the restraint system (SRS). It processes the signals of the crash sensors, decides in an accident on airbags and seatbelt pretensioners, and monitors the system continuously. After an accident, it stores crash data and locks itself.

The unit passes system faults on to the airbag warning light in the instrument cluster. This makes a fault visible to the driver.

Why does the control unit 28556-3SV0A fail?

The most common cause is stored crash data, even if no airbag has deployed; a normal diagnostic tool does not remove it. Other causes are ageing electronic components, cold solder joints, moisture and corrosion at plugs, and voltage spikes, for example from a weak battery or jump start.

Stored crash data remains in the unit after the event, even if the airbags were not affected. Removing it is done by the repair at Airbag24.

The other causes mainly concern the connections and the electronics. Plugs that draw in moisture, soldered joints that stayed cold, and voltage spikes from the vehicle's power supply all belong here.

How can you tell that the 28556-3SV0A is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently, fault messages appear, and the diagnostic tool cannot reach the control unit. If the fault memory cannot be cleared, this confirms the finding. In an emergency, airbags and seatbelt pretensioners may then not be able to deploy.

The airbag warning light is the most direct indication you get from the restraint system, which is why it takes precedence over all other signs.

Which vehicles is the 28556-3SV0A fitted in?

The 28556-3SV0A is fitted in these vehicles: Nissan Sylphy B17 (from 2012).

The assignment to vehicles is shown in this list:

• Nissan Sylphy B17 (from 2012)

Compare the part number on the label of the removed unit with this page; that only settles the question of the right unit. Also have the fault memory read out beforehand, because only its contents show whether the control unit or a plug or cable is the cause.

How does the repair of the 28556-3SV0A work?

First enclose the log of the read-out fault memory, then disconnect the battery and remove the control unit. Then create a repair order online and pack the unit well. Airbag24 usually needs 3–4 working days for testing, repairing and checking.

At Airbag24, the workshop checks the control unit on the test bench, replaces defective components, erases the crash data and carries out a function test. Your own unit then goes back 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 28556-3SV0A get to Airbag24?

You send the unit in as a parcel, or you book a UPS collection for an extra charge. Airbag24 sends the repaired unit back by UPS.

The printed repair order goes into the parcel. Pack the unit shockproof so that it arrives undamaged.