Airbag control unit with part number 28556-JC20B

What does the airbag control unit 28556-JC20B do?

For Nissan, the airbag control unit 28556-JC20B coordinates the restraint system (SRS). It evaluates the signals from the crash sensors, decides in an accident in the blink of an eye which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. It shows faults via the airbag warning light.

Monitoring is a continuous task of the control unit. The unit stores irregularities in the fault memory, where a workshop or a diagnostic tool can read them out.

After an accident, the unit stores crash data and locks itself.

Why does the control unit 28556-JC20B fail?

Stored crash data, even if no airbag has deployed, is the most common cause on the 28556-JC20B. Aged electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes are also possible. With this control unit, deleting the crash data is often not possible; if you would like the crash data deleted, contact Airbag24 briefly before sending the unit in, so that it can check the part number.

Crash data are records of the accident that the control unit stores after the accident.

The other causes mainly concern the electronics themselves. Components age over time, and cold solder joints on the circuit board can cause contact problems.

Moisture and corrosion at plug connectors disrupt the connection, and voltage spikes, for example from a weak battery or a jump start, put a strain on the electronics.

How can you tell that the 28556-JC20B is defective?

The airbag warning light in the instrument cluster lights up on the 28556-JC20B, either permanently or intermittently. In addition, the instrument cluster shows a fault message, and a diagnostic tool gets no connection to the control unit.

Look out for the following signs:

• Airbag warning light lights up permanently or intermittently
• Fault message in the instrument cluster
• Diagnostic tool gets no connection to the control unit
• Fault memory cannot be cleared

In an emergency, the airbags and seatbelt pretensioners may then fail to deploy. Therefore, take the warning signal seriously.

Which vehicles is the 28556-JC20B fitted in?

The control unit 28556-JC20B is fitted in these vehicles: Nissan Teana J32 (2008-2013). Use the list to check whether your vehicle is included.

The vehicles are recorded in this list:

• Nissan Teana J32 (2008-2013)

Compare the part number on the label of the removed unit with this page. This only makes sure that it is the right unit. Also have the fault memory read out before removal, because only this result 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 98820 JN50A.

How does the repair of the 28556-JC20B work?

First have the fault memory read out and enclose the log, then disconnect the battery and remove the control unit. Then create a repair order online and send the unit in, well packed. Airbag24 checks the 28556-JC20B on the test bench, replaces defective components and carries out a function test; processing at Airbag24 usually takes 3–4 working days.

Keep to the order without fail, because it serves the safety of the vehicle.

If you would like the crash data deleted, 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-JC20B get to Airbag24?

You send the control unit 28556-JC20B in as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

Put the printed repair order into the parcel and pack the unit shockproof.