Airbag control unit with part number A0048203010

What does the airbag control unit A0048203010 do?

The airbag control unit A0048203010 controls the restraint system (SRS) of Mercedes-Benz: it analyses the signals from the crash sensors and decides within milliseconds in the event of an accident which airbags and seatbelt pretensioners are triggered. After an accident it stores crash data and locks itself.

While you are driving, the unit monitors the entire system continuously. If it detects a fault, it reports this via the airbag warning light in the instrument cluster, so that you can keep an eye on the state of the system.

The crash sensors send their measurements to the control unit, which evaluates them in fractions of a second. This evaluation is precisely what determines how quickly the system reacts in an emergency.

Why does the control unit A0048203010 fail?

Most often the cause is crash data from an earlier accident, even if no airbag deployed; a standard diagnostic tool cannot erase it. Other causes include ageing electronic components, cold solder joints, moisture and corrosion on plug connections, and voltage spikes, for example from a weak battery or a jump start.

After an accident the unit records data about that event, even if the airbags remain unchanged. Airbag24 erases this crash data during the repair, so you do not need to do anything yourself for it.

The other causes act over a longer period: moisture and corrosion attack the plug connections, solder joints age, and voltage spikes can damage components.

How can you tell that the A0048203010 is defective?

A defect in the A0048203010 shows up as the airbag warning light in the instrument cluster, which lights up permanently or intermittently. A fault message in the instrument cluster, no connection to the diagnostic tool, or a fault memory that cannot be cleared also point to a defect. In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

The signs vary depending on the cause. Pay attention to each of these hints, even if it appears only occasionally.

• airbag warning light that lights up permanently
• airbag warning light that lights up intermittently
• fault message in the instrument cluster
• no connection to the diagnostic tool
• fault memory that cannot be cleared

If you notice any of these signs, have the system checked promptly by a workshop with a diagnostic tool.

Which vehicles is the A0048203010 fitted in?

The control unit A0048203010 is part of the equipment of vehicles of the make Mercedes-Benz. It is fitted in these vehicles: Mercedes-Benz S-Class W140 Saloon (1991-1998).

The vehicles at a glance:

• Mercedes-Benz S-Class W140 Saloon (1991-1998)

Before removal, compare the part number on the label of the unit with this page; this only ensures that you have the correct unit in front of you. Also have the fault memory read out beforehand. Only the log shows whether the control unit is defective or whether a connector or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 8209726, A 000 820 80 26 (00), A 004 820 17 10, A0018200826, A0018201926.

How does the repair of the A0048203010 work?

First you read out the fault memory and enclose the log, then you disconnect the battery and only then remove the control unit. Afterwards you create a repair order online and send the unit in, well packed. Airbag24 checks it on the test bench, replaces defective components, erases stored crash data and carries out a function test; after that your own unit is returned to you.

Processing at Airbag24 usually takes 3–4 working days. This time covers only the checking, repairing and testing at Airbag24; reading out, removal and dispatch are not included.

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 A0048203010 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 to you by UPS.

Put the printed repair order into the parcel and use shock-proof packaging so that the unit remains undamaged in transit.