Airbag control unit with part number A2048709626

What does the airbag control unit A2048709626 do?

The airbag control unit A2048709626 is the central switching point of the restraint system (SRS) in Mercedes-Benz. It evaluates the crash sensors and decides which airbags and seatbelt pretensioners are triggered.

Evaluation and decision take place within milliseconds. The unit monitors the system continuously and shows faults via the airbag warning light.

After an accident it stores crash data and locks itself.

Why does the control unit A2048709626 fail?

Stored crash data is the most common cause when the A2048709626 fails, even if no airbag has deployed. It cannot be erased with a normal diagnostic tool. Aged components, cold solder joints, moisture, corrosion and voltage spikes can also contribute to failure.

The crash data remains in the control unit until Airbag24 erases it during repair.

The other causes concern the electronics and the connections, such as plug contacts attacked by moisture. Voltage spikes arise, for example, with a weak battery or when jump-starting.

How can you tell that the A2048709626 is defective?

The airbag warning light in the instrument cluster indicates a defect in the A2048709626 as soon as it lights up permanently or intermittently. In addition there are fault messages in the instrument cluster, no connection to the diagnostic tool, or a fault memory that cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may then not deploy.

These signs require a check of the system, even if the vehicle otherwise seems unremarkable.

Which vehicles is the A2048709626 fitted in?

The A2048709626 is fitted in these vehicles: Mercedes-Benz C-Class S204 Estate (2007-2014), W204 Saloon (2007-2014) and C204 Coupé (2011-2015).

The list shows the models in which this part number is fitted:

• Mercedes-Benz C-Class S204 Estate (2007-2014)
• Mercedes-Benz C-Class W204 Saloon (2007-2014)
• Mercedes-Benz C-Class C204 Coupé (2011-2015)

Comparing the part number on the label of the removed unit with this page only confirms the right unit. The fault memory must be read out in advance, because only it shows whether the control unit is defective or whether a plug or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 2048709426, 5WK44740, A204 870 68 26, A204 901 26 04, A204 901 35 02, A2048208285.

How does the repair of the A2048709626 work?

You read out the fault memory, attach the log, disconnect the battery and only then remove the A2048709626. Then you create a repair order online and send the unit in well packed. At Airbag24, checking, repair and testing usually take 3–4 working days.

Airbag24 checks the control unit on the test bench, replaces defective components, erases the stored crash data and carries out a function test.

Afterwards your own unit goes back 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 A2048709626 get to Airbag24?

The control unit A2048709626 reaches Airbag24 as a parcel or via a UPS collection booked for an extra charge. The return after repair is by UPS.

Include the printed repair order in the parcel and pack the unit shock-resistant.