Airbag control unit with part number DF73-57K30-C

What does the airbag control unit DF73-57K30-C do?

The airbag control unit DF73-57K30-C is the central control unit of the restraint system (SRS) of Mazda. It evaluates the signals of the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners are triggered. After an accident, it stores crash data and locks itself.

In everyday use, the unit checks the entire system without interruption. If it detects a fault, it shows this via the airbag warning light in the instrument cluster.

This includes the sensors, the wiring and the connected components, which the control unit monitors continuously.

Why does the control unit DF73-57K30-C fail?

The most common cause on control unit DF73-57K30-C is crash data stored after an accident, even if no airbag has deployed. Other causes are aged components, cold solder joints, moisture on plugs and voltage spikes.

The crash data remains in memory until the repair erases it. A standard diagnostic tool cannot reach it and cannot remove the data.

Besides the crash data, further causes may apply:

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

How can you tell that the DF73-57K30-C is defective?

The airbag warning light in the instrument cluster indicates a defect on the DF73-57K30-C when it lights up permanently or intermittently. An error message in the instrument cluster appears alongside it, the diagnostic tool cannot find the control unit, and the fault memory cannot be cleared.

While the light is on, airbags and seatbelt pretensioners may not deploy in an emergency. This indication must therefore not be ignored, even if the vehicle runs normally in everyday use.

If no connection to the diagnostic tool can be made, that is another sign that something in the system is wrong.

Which vehicles is the DF73-57K30-C fitted in?

The control unit DF73-57K30-C is fitted in these vehicles: Mazda Mazda2 DE (2007-2010) and DE Facelift (2010-2014).

Here you can see the vehicles at a glance:

• Mazda Mazda2 DE (2007-2010)
• Mazda Mazda2 DE Facelift (2010-2014)

Comparing the part number on the label of the removed unit with this page makes sure that you have the correct unit. That comparison says nothing more. Therefore, have the fault memory read out beforehand, because only this result 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 2S6T-14B056-EN, DF73-57K30B, GC1M-57-K30.

How does the repair of the DF73-57K30-C work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit DF73-57K30-C. Next, create a repair order online and pack the unit well. At Airbag24, testing, repair and function test usually take 3–4 working days.

This order is mandatory for safety reasons. Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. 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 DF73-57K30-C get to Airbag24?

You send the control unit DF73-57K30-C as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns the unit to you by UPS.

Put the printed repair order in the parcel and pack the control unit shock-proof.