Airbag control unit with part number BFG8-57K30

What does the airbag control unit BFG8-57K30 do?

The airbag control unit BFG8-57K30 is the central control unit of the SRS restraint system for Mazda. It evaluates the crash sensors, decides within milliseconds in an emergency which airbags and seatbelt pretensioners are triggered, and monitors the entire system.

Faults are shown via the airbag warning light in the instrument cluster, so that you notice them immediately.

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

Why does the control unit BFG8-57K30 fail?

The most common cause is crash data from an accident, even without a deployed airbag; a normal diagnostic tool cannot erase it. Other causes are ageing electronics, cold solder joints, moisture and voltage spikes.

An accident without deployment can therefore still leave consequences in the memory.

• ageing electronic components
• cold solder joints
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery

The exact cause is determined only by reading out the fault memory.

How can you tell that the BFG8-57K30 is defective?

The airbag warning light in the instrument cluster lights up constantly or intermittently, and fault messages appear. In addition, the fault memory cannot be cleared or the diagnostic tool finds no connection to the control unit. In an emergency, airbags and seatbelt pretensioners may then not be able to trigger.

• Airbag warning light that stays on or lights up intermittently
• Fault message in the instrument cluster
• Diagnostic tool without a connection to the control unit
• Fault memory that cannot be cleared

These signs point to a defect as soon as they occur. The warning light is the clearest signal.

Whether the control unit itself or the wiring is affected is determined only by the diagnosis.

Which vehicles is the BFG8-57K30 fitted in?

The BFG8-57K30 is fitted in these vehicles: Mazda Mazda3 BL (2009-2011) and BL Facelift (2011-2013).

The following vehicles are on record for this part number:

• Mazda Mazda3 BL (2009-2011)
• Mazda Mazda3 BL Facelift (2011-2013)

Comparing the part number on the label of the removed unit with this page only confirms that it is the right unit. Have the fault memory read out beforehand; that 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 0 285 001 960, B39G-57K30, BCF1-57K30, BFB6-57-K30, BFD1-57K30.

How does the repair of the BFG8-57K30 work?

First have the fault memory read out and enclose the log with the parcel; then disconnect the battery and only then remove the control unit. Create a repair order online and send in the well-packed unit. Processing at Airbag24 usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. The unit then comes back 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 BFG8-57K30 get to Airbag24?

You send the unit off as a parcel, or have it collected by UPS for an extra charge. After the repair Airbag24 returns it to you by UPS.

Enclose the printed repair order before you close the box; the unit must be packed shockproof.