Airbag control unit with part number A2079010200

What does the airbag control unit A2079010200 do?

The airbag control unit A2079010200 is the central control unit of the restraint system (SRS) for Mercedes-Benz. It evaluates the crash sensors, decides in an emergency within milliseconds on the triggering of airbags and seatbelt pretensioners, and monitors the overall system.

The control unit runs constantly and checks connections, sensors and actuators. It stores detected faults in the fault memory and displays them via the airbag warning light in the instrument cluster.

After an accident it stores crash data and locks itself. The following sections describe where that comes from and what it means for the repair.

Why does the control unit A2079010200 fail?

The most common cause is crash data stored after an accident, even if no airbag was triggered. A normal diagnostic tool cannot erase this data.

Such data stays in the unit, even if the vehicle seems inconspicuous afterwards. The result is a fault that cannot be cleared with common tools, and that is exactly why the problem can be pushed onto other components for too long.

In addition, aged electronic components, moisture and corrosion at plug connections, and voltage spikes come into question. A weak battery or jump starting can also affect the unit.

How can you tell that the A2079010200 is defective?

A defect shows itself through an airbag warning light that stays on permanently or intermittently, an error message in the instrument cluster, or a diagnostic tool that cannot establish a connection. If the fault memory keeps the entry, the suspicion becomes more concrete.

The airbag warning light can give the first indication. It can stay on permanently or light up only intermittently, and both mean the system is not fully working. An error message in the instrument cluster can confirm this.

In an emergency airbags and seatbelt pretensioners may fail to trigger as long as the fault persists. The cause should therefore be clarified promptly.

Which vehicles is the A2079010200 fitted in?

The control unit A2079010200 is fitted in these vehicles: Mercedes-Benz E-Class C207 Coupé (2009-2016) and A207 Convertible (2010-2017).

For an overview, we list here the models for which this part number is documented.

• Mercedes-Benz E-Class C207 Coupé (2009-2016)
• Mercedes-Benz E-Class A207 Convertible (2010-2017)

Before removal, have the fault memory read out. That establishes whether the control unit is really affected or whether a plug or cable triggers the message. Then compare the part number on the label with the information here.

For the same vehicles, we also repair control units with the part numbers 2079011700, A2078203226, A2079010100, A212 901 85 08.

How does the repair of the A2079010200 work?

Before removal, read out the fault memory and attach the log. Then disconnect the battery, remove the control unit and create the repair order online before you send it in.

At Airbag24 the unit is checked on the test bench, defective components are replaced, the crash data is deleted and a function test follows. Processing usually takes 3–4 working days.

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 A2079010200 get to Airbag24?

You send the control unit A2079010200 as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends it back to you by UPS.

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