Airbag control unit with part number 28556-9CG0A

What does the airbag control unit 28556-9CG0A do?

The airbag control unit 28556-9CG0A is the central control unit of the restraint system (SRS) of Nissan. It evaluates the signals from the crash sensors, decides in an accident whether airbags and seatbelt pretensioners are triggered, and monitors the system continuously. After an accident it locks itself, and only a repair lifts this lock.

The control unit also stores events in the fault memory. A failure therefore does not affect individual parts alone, but the entire interplay of sensors, airbags and seatbelt pretensioners.

Via the instrument cluster, the control unit passes messages on to the driver as soon as something in the system is not right.

Why does the control unit 28556-9CG0A fail?

The most common cause is crash data stored after an accident, even without a triggered airbag. A normal diagnostic tool cannot erase them. Aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes are also possible causes.

Crash data is the record of an event. It remains in the memory, and only the repair removes it.

Electronic components lose stability over time, and solder joints can go cold or crack. Moisture and corrosion attack the contacts, and voltage spikes arise, for example, from a weak battery or a jump start.

How can you tell that the 28556-9CG0A is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently, an error message appears, the diagnostic tool finds no control unit, and the fault memory cannot be cleared.

Typical signs are:

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

In an emergency, airbags and seatbelt pretensioners may then fail to deploy. The display is therefore a reason to have the system checked promptly.

Which vehicles is the 28556-9CG0A fitted in?

The control unit 28556-9CG0A is fitted in these vehicles: Nissan Xterra N50 (2005-2008) and N50 Facelift (2008-2015).

The matching models are listed below.

• Nissan Xterra N50 (2005-2008)
• Nissan Xterra N50 Facelift (2008-2015)

First compare the part number on the label of the removed unit with this page. This only ensures that it is the right unit. Then have the fault memory read out, because the log shows whether the control unit is defective or whether a connector or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 28556-EC00B, 98820-AV200, 98820-AV21A, 98820-ZP31A.

How does the repair of the 28556-9CG0A work?

First read out the fault memory and enclose the log, then disconnect the battery and only then remove the control unit 28556-9CG0A. Next, create the repair order online and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days.

At Airbag24 the test bench checks the unit, replaces defective components, erases stored crash data and carries out a function test. Then your own unit comes back.

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 28556-9CG0A get to Airbag24?

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

Enclose the printed repair order and pack the control unit shock-proof.