Airbag control unit with part number 98820-4MA0B

What does the airbag control unit 98820-4MA0B do?

The airbag control unit 98820-4MA0B evaluates, in the restraint system (SRS) of Nissan, the signals from the crash sensors. In an accident it decides within milliseconds which airbags and seatbelt pretensioners trigger, and then monitors the entire system. It shows faults via the airbag warning light.

After an accident the unit stores crash data and locks itself. All messages from the restraint system converge in the control unit.

Why does the control unit 98820-4MA0B fail?

The most common cause for 98820-4MA0B is crash data stored after an accident, even if no airbag has deployed. Other causes are aged components, cold solder joints, moisture and corrosion at connectors, and voltage spikes.

Crash data remains in the unit after an impact, and it cannot be deleted with a standard diagnostic tool, which is why Airbag24 removes it during the repair.

The other causes act on the electronics through ageing, moisture or voltage. Solder joints, plug contacts and the supply voltage are the points where this shows.

How can you tell that the 98820-4MA0B is defective?

A defect in 98820-4MA0B shows itself through the airbag warning light in the instrument cluster, which is on permanently or intermittently, and through fault messages. The diagnostic tool cannot find the control unit, and the fault memory cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

A light that does not go out after the ignition is switched on reports a fault in the system to the driver.

A fault that occurs only intermittently is also displayed this way. In that case, it is worth having the fault memory read before anything is removed.

Which vehicles is the 98820-4MA0B fitted in?

The airbag control unit 98820-4MA0B is fitted in these vehicles: Nissan Sylphy B17 (from 2012).

This list shows which models belong to it:

• Nissan Sylphy B17 (from 2012)

Compare the part number on the label of the removed unit with this page. This only confirms that it is the correct unit, nothing more. Have the fault memory read out beforehand, 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 28556-3RA0A, 28556-3RB0A, 28556-3RC0A, 28556-3RD0B, 28556-3RF0B, 28556-3RL0A.

How does the repair of the 98820-4MA0B work?

For 98820-4MA0B, the sequence is: first have the fault memory read out and attach the log, then disconnect the battery and only then remove the unit. Online, create the repair order, then send in the well-packed unit. Testing, repair and function test there usually take 3–4 working days.

Inside Airbag24's premises the control unit is examined on the test bench and defective components are replaced. Afterwards Airbag24 deletes the stored crash data, carries out a function test and sends your own unit 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 98820-4MA0B get to Airbag24?

You arrange the shipment yourself, either by parcel or with a UPS collection for 98820-4MA0B booked for an extra charge. The return after the repair is also made by UPS.

Pack the unit shockproof and enclose the printed repair order.