Airbag control unit with part number K30F-57K30

What does the airbag control unit K30F-57K30 do?

The control unit K30F-57K30 controls the SRS restraint system in Mazda. Its task is to evaluate messages from the impact sensors and determine the appropriate trigger within milliseconds. A fault in the sequence appears as a warning on the airbag warning light.

While driving, the unit continuously monitors the connected components and records irregularities.

After an accident it secures crash data and then locks itself. The data remain in the unit afterwards.

Why does the control unit K30F-57K30 fail?

Stored crash data after an accident is the most common cause, even if no airbag has been triggered. A conventional reader cannot remove it. Ageing and moisture in the electronics also come into question as causes.

• ageing electronic components
• cold solder joints
• corrosion and moisture on plug connectors
• voltage spikes, for example with a weak battery or jump-starting

Airbag24 deletes crash data as part of the repair, so this point is taken care of during processing.

Which of the other points applies is shown only by the investigation.

How can you tell that the K30F-57K30 is defective?

A permanently or intermittently lit airbag warning light in the instrument cluster is the typical sign. In addition there are error messages in the instrument cluster, a missing connection between the diagnostic tool and the control unit, and a fault memory that cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then not deploy.

The warning light is a direct indication from the system of a fault. React to it promptly rather than waiting.

A diagnostic tool that cannot establish a connection does not by itself reveal the cause. Only reading out the fault memory clarifies the situation.

Which vehicles is the K30F-57K30 fitted in?

The control unit K30F-57K30 is fitted in these vehicles: Mazda CX-5 KF (2017-2021) and KF Facelift (from 2021).

Here follows the list of vehicles:

• Mazda CX-5 KF (2017-2021)
• Mazda CX-5 KF Facelift (from 2021)

Before removal, check the part number on the label against this page so that you know for certain it is the right unit. Also have the fault memory read out before you remove anything; only that shows whether the control unit is defective or whether a plug and cable are the cause.

For the same vehicles, we also repair control units with the part numbers 0 285 014 556 Bosch, K123 57K K2 B, K123 57K30 A, K123 57K30 B, KA1C-57-K30A, KD47-57-K50.

How does the repair of the K30F-57K30 work?

Have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit. Afterwards create a repair order online and send the unit in well packed. Airbag24 checks it on the test bench, replaces defective components, deletes crash data and carries out a function test; processing usually takes 3–4 working days.

The log is part of the consignment so that the finding is on record. Afterwards your own unit is returned 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 K30F-57K30 get to Airbag24?

Either you send the control unit K30F-57K30 in as a parcel yourself, or you book a UPS collection for an extra charge. The return after the repair is made by UPS.

Enclose the printed repair order in the parcel, and the unit must be packed shock-proof.