Airbag control unit with part number EH70-57K30-A

What does the airbag control unit EH70-57K30-A do?

The airbag control unit EH70-57K30-A controls the restraint system (SRS) of Mazda. It evaluates the signals from the crash sensors, decides within milliseconds in a crash whether airbags and seatbelt pretensioners are triggered, and monitors the system continuously.

If the unit detects a fault, it reports it via the airbag warning light in the instrument cluster. This makes the state of the system readable for the driver and the workshop.

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

Why does the control unit EH70-57K30-A fail?

Stored crash data is the most common cause, after an accident even when no airbag has deployed. This data cannot be removed with a standard diagnostic tool, so the control unit remains flagged.

Other causes are aged electronic components, cold solder joints, moisture and corrosion at the plug connections, and voltage spikes. A weak battery or a jump start can trigger such spikes.

Airbag24 erases the crash data during the repair and checks the other causes at the same time.

How can you tell that the EH70-57K30-A is defective?

The airbag warning light points directly to the defect: it stays on or comes on intermittently. An error message also appears in the instrument cluster. In addition, the diagnostic tool cannot establish a connection to the control unit, and the fault memory cannot be cleared. In an emergency, the airbags and seatbelt pretensioners may then fail to deploy.

These signs can occur together, but they do not have to. The warning light alone is already a reason to have the system checked.

Which vehicles is the EH70-57K30-A fitted in?

The control unit EH70-57K30-A is fitted in these vehicles: Mazda CX-7 ER (2006-2009) and ER Facelift (2009-2012).

These models are stored for the part number. Use them to check your vehicle:

• Mazda CX-7 ER (2006-2009)
• Mazda CX-7 ER Facelift (2009-2012)

Compare the part number on the label of the removed unit with this page, and you will know that you have the right unit. The comparison tells you nothing more. Have the fault memory read out before you remove the control unit. Only the log shows whether the control unit itself is the cause or whether a plug or cable is.

For the same vehicles, we also repair control units with the part numbers 0J14A3906642, 9H05A3906641.

How does the repair of the EH70-57K30-A work?

At Airbag24, processing usually takes 3–4 working days. Beforehand, you have the fault memory read out and attach the log. Then you disconnect the battery, and only after that do you remove the control unit. Finally you send it in after creating a repair order online, well packed.

After that, Airbag24 takes over. The unit is checked on the test bench, defective components are replaced and the crash data is erased. A function test follows before your own unit is sent back.

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 EH70-57K30-A get to Airbag24?

The unit reaches Airbag24 as a parcel, or you book a UPS collection for an extra charge. The return after the repair is made by UPS.

Put the printed repair order into the parcel. Pack the unit shockproof so that it arrives undamaged.