Airbag control unit with part number DF71-57K30-C

What does the airbag control unit DF71-57K30-C do?

The airbag control unit DF71-57K30-C is the central control unit of the restraint system (SRS) for Mazda. It evaluates the signals from the crash sensors and decides in a crash, within milliseconds, which airbags and seatbelt pretensioners are triggered. After an accident it stores crash data and locks itself.

During operation the unit monitors the entire system continuously. If it detects a deviation, it creates a fault entry and reports it via the airbag warning light in the instrument cluster.

The stored data is also important for diagnosis. Without evaluating the fault memory, a fault can hardly be narrowed down.

Why does the control unit DF71-57K30-C fail?

Crash data stored after an accident is the most common cause, even if no airbag has triggered; a normal diagnostic tool cannot erase it. Other causes include aged electronic components, cold solder joints, moisture and corrosion on plug connections, and voltage spikes.

Airbag24 deliberately erases the stored crash data during the repair. The erasure is therefore a fixed part of the repair process.

The other causes develop over time: components age, solder joints can become cold, and moisture attacks contacts. Voltage spikes arise, for example, from a weak battery or from starting with external power.

How can you tell that the DF71-57K30-C is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, and an error message appears in the instrument cluster. In addition, the diagnostic tool cannot connect and the fault memory cannot be cleared.

With these signs, airbags and seatbelt pretensioners may not trigger in a crash. Even a light that comes on only now and then should be taken seriously.

Have the fault memory read out, because only this result makes the cause visible.

Which vehicles is the DF71-57K30-C fitted in?

The control unit DF71-57K30-C is fitted in these vehicles: Mazda Mazda2 DE (2007-2010) and DE Facelift (2010-2014). The details come from our data on this unit.

Here are the vehicles for which we hold this control unit:

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

Compare the part number on the label of the removed unit with this page. This only confirms that you have the right unit. Also have the fault memory read out beforehand, because only this log shows whether the control unit itself 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 DF71-57K30-C work?

First read out the fault memory and enclose the log, then disconnect the battery and only then remove the control unit. Afterwards create a repair order online and send in the well-packed unit.

Airbag24 checks the unit on the test bench, replaces defective components, erases the stored crash data and carries out a function test. Afterwards your own unit is returned to you.

Processing at Airbag24 usually takes 3–4 working days; this period covers only checking, repairing and testing. 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 DF71-57K30-C get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it by UPS.

Put the printed repair order into the parcel and pack the control unit shockproof.