Airbag control unit with part number NA1J-57K30B

What does the airbag control unit NA1J-57K30B do?

The airbag control unit NA1J-57K30B is the central control unit of the restraint system (SRS) at Mazda. It processes the signals from the crash sensors, decides in an accident within milliseconds on the triggering of airbags and seatbelt pretensioners, and monitors the system constantly. If it detects a fault, it reports it via the airbag warning light.

Monitoring runs in the background while the vehicle is in operation.

After an accident the unit records crash data and is locked afterwards.

Why does the control unit NA1J-57K30B fail?

On the NA1J-57K30B, stored crash data from an accident is the most common cause, even if no airbag fired. Other factors include aged components, moisture at plug connectors, cold solder joints and voltage spikes. A normal diagnostic tool cannot erase the crash data.

Airbag24 erases the crash data during the repair, so you do not need to take this step yourself.

Electronic components age, moisture attacks plug connectors, cold solder joints can disrupt contacts, and voltage spikes occur, for example, with a weak battery or after a jump start.

How can you tell that the NA1J-57K30B is defective?

A defect on the NA1J-57K30B shows as the airbag warning light in the instrument cluster, which is lit permanently or intermittently. Added to this are a fault message in the instrument cluster, no connection to the diagnostic tool, or a fault memory that cannot be cleared.

The warning light is the signal you should watch for first. It indicates the defect as soon as the system detects it.

As long as the fault exists, the airbags and seatbelt pretensioners may not be able to fire in an emergency. Therefore have the vehicle taken to a workshop promptly.

Which vehicles is the NA1J-57K30B fitted in?

The airbag control unit NA1J-57K30B is fitted in these vehicles: Mazda MX-5 ND (from 2015).

The affected models are listed here:

• Mazda MX-5 ND (from 2015)

Compare the part number on the label of the removed unit with this page, and then you know you have the right unit in front of you. But have the fault memory read out beforehand: only this finding shows whether the control unit is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 0 285 014 161 Bosch, N243 57K K2 C, N243 57K30 A, N243 57K30 C, N243 57K30 D, N243-57-K30G.

How does the repair of the NA1J-57K30B work?

First have the fault memory read out and the log attached to the unit. Then disconnect the battery and only then remove the control unit NA1J-57K30B. Create the repair order online and pack the unit well before sending it.

Airbag24 examines the unit on the test bench, replaces defective components, removes stored crash data and carries out a function test. Checking, repairing and testing at Airbag24 usually take 3–4 working days.

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. Afterwards your unit is returned to you.

How does the control unit NA1J-57K30B get to Airbag24?

Your control unit NA1J-57K30B reaches Airbag24 in a parcel or via a UPS collection booked for an extra charge. The return after the repair is made by UPS. The printed repair order goes into the parcel.

Pay attention to shock protection when packing so that the unit does not shift in the parcel.