Airbag control unit with part number 985107072R

What does the airbag control unit 985107072R do?

The airbag control unit 985107072R controls the restraint system (SRS) of Smart. It measures the deceleration via the crash sensors, decides in an accident within milliseconds on the triggering of airbags and seatbelt pretensioners, and checks the system continuously.

It signals faults via the airbag warning light. After an accident it stores crash data and locks itself.

This makes the unit the link between sensors and triggering elements, and its function is fundamental to the safety of the occupants.

Why does the control unit 985107072R fail?

The most common cause for 985107072R is crash data stored after an accident, even without an airbag having triggered. Ageing components, cold solder joints, moisture and corrosion, and voltage spikes in the vehicle electrical system are further causes.

Crash data remains stored after the accident, even if no airbag has deployed. It cannot be deleted with a standard diagnostic tool, and Airbag24 removes it during the repair.

The other causes concern the electronics themselves. Components age, solder joints can turn cold, and moisture or corrosion on the plugs impairs contact. A weak battery or jump-starting can cause additional voltage spikes.

How can you tell that the 985107072R is defective?

A defect at the 985107072R shows up through the airbag warning light in the instrument cluster, through a fault message in the instrument cluster, through a missing connection of the diagnostic tool to the control unit, and through a fault memory that cannot be cleared.

The airbag warning light in the instrument cluster is among the most important indicators in the vehicle. It lights up permanently or only intermittently and points to a fault in the restraint system that you should have checked.

If no connection to the control unit is established or the fault memory stays unchanged, this also indicates a fault. Airbags and seatbelt pretensioners may then not be able to trigger in an emergency.

Which vehicles is the 985107072R fitted in?

The control unit 985107072R matches the models on record for Smart. It is fitted in these vehicles: Smart Fortwo C453 (2014-2024).

The known vehicles with this part number are listed in the following list.

• Smart Fortwo C453 (2014-2024)

Comparing the label of the removed unit with this page only shows the identity of the unit. Whether the control unit is defective or a plug or cable is the cause is shown only by the fault memory read out beforehand.

For the same vehicles, we also repair control units with the part numbers A453 901 89 00, A4539001702, A4539017400.

How does the repair of the 985107072R work?

First have the fault memory read out and enclose the log, then disconnect the battery, remove the control unit 985107072R and create the repair order online before you send the unit. At Airbag24, testing, repair and testing usually take 3–4 working days.

The order is fixed for safety reasons. A sturdy carton with padding keeps the unit in position on the way.

Airbag24 examines the unit on the test bench, replaces defective components, deletes the stored crash data and carries out a function test.

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 985107072R get to Airbag24?

Sending takes place as a parcel or with a UPS collection booked for an extra charge. After the repair Airbag24 returns the control unit 985107072R by UPS.

Print out the repair order, place it in the parcel, and pack the unit shock-proof.