Airbag control unit with part number DN20-57K30

What does the airbag control unit DN20-57K30 do?

The airbag control unit DN20-57K30 is the control centre of the restraint system (SRS) of Mazda. It evaluates the signals from the crash sensors, decides on triggering airbags and seatbelt pretensioners in a collision, and monitors the system continuously. After an accident it stores crash data and locks itself.

The unit reports faults via the airbag warning light in the instrument cluster, so the state of the system remains readable.

Why does the control unit DN20-57K30 fail?

The most common cause on the DN20-57K30 is crash data stored after an accident, even if no airbag has deployed. A normal diagnostic tool does not make it disappear. Aged components, cold solder joints, moisture and corrosion, and voltage spikes are also possible causes.

Stored crash data stays in the unit until Airbag24 erases it during the repair.

The other triggers come from ageing, moisture and voltage fluctuations in the vehicle electrics, for example with a weak battery.

How can you tell that the DN20-57K30 is defective?

A defect in the DN20-57K30 shows up as an airbag warning light that stays on permanently or intermittently, as error messages in the instrument cluster, as a lack of connection to the diagnostic tool, and as a fault memory that cannot be cleared.

• Airbag warning light stays on permanently or intermittently
• Error message in the instrument cluster
• Diagnostic tool receives no connection to the control unit
• Fault memory cannot be cleared

In an emergency, airbags and seatbelt pretensioners may not deploy. Please check these signs promptly.

Which vehicles is the DN20-57K30 fitted in?

Several vehicles are assigned to this unit. It is fitted in these vehicles: Mazda Mazda2 DE (2007-2010) and DE Facelift (2010-2014).

This assignment is listed here:

• 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 or 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 DN20-57K30 work?

First have the fault memory read out and attach the log. Then disconnect the battery and only then remove the control unit DN20-57K30. Afterwards create a repair order online and send in the well-packed unit. Airbag24 usually needs 3–4 working days for testing, repair and checking.

On the test bench, Airbag24 checks the unit, replaces defective components, erases the crash data and runs 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 DN20-57K30 get to Airbag24?

The control unit DN20-57K30 reaches Airbag24 either as a parcel or through a UPS collection that is booked for an extra charge. After the repair, the return is made by UPS.

The printed repair order is included in the parcel; the unit itself is packed shock-proof.