Smart #3 airbag control unit repair⁽¹⁾

What should I bear in mind with Smart #3 airbag control units?

The Smart #3 airbag control unit evaluates the crash sensors, triggers the airbags and belt tensioners, and reports faults via the airbag warning light. After an accident it stores crash data and locks itself. A defective control unit should therefore be checked by a specialist workshop.

The control unit manages a safety-relevant system. A fault affects whether the airbags trigger in a crash, and the airbag warning light shows it. Diagnosis and any work on the system should therefore be left to a specialist workshop, not carried out yourself.

Airbag24 repairs the control unit of your own Smart #3 that you send in. The crash data is erased, and the unit is checked, repaired and then tested.

Which Smart #3 generations are there?

Our overview lists three series for the Smart #3: Brabus, Premium and Pro. The series differ mainly in drivetrain and equipment.

Check the series and model year of your vehicle using the vehicle documents and the vehicle identification number (VIN).

• Brabus – version with all-wheel drive, where a second motor is added on the front axle
• Premium – version with a rear motor and its own equipment line
• Pro – version with a rear motor

How do I identify my Smart #3 airbag control unit?

The part number on the label of the control unit shows the exact version. Model year and equipment of your Smart #3 are also important and can be matched using the vehicle identification number (VIN).

The part number is often printed directly on the housing of the control unit. It shows the exact version, but it does not replace a check against model year and equipment. If in doubt, a workshop will help with the assignment.

Fault codes are a first clue. For example, the codes B1000, U1013, U1123 or U1400 may be stored in the fault memory. A single code, however, does not prove a defect in the control unit; only a check in the workshop shows the cause.

Which airbag equipment does Smart #3 have?

According to safety assessments, the Smart #3 has front airbags for driver and front passenger. ANCAP also lists side airbags for chest and head areas as standard. According to the European NCAP test, no knee airbags are provided for the front seats.

Equipment can vary by market and series. The equipment list of your vehicle shows which airbags are fitted.

The route to repair works like this: first have the fault memory read, so it is clear which faults the system has reported. Disconnecting the battery and removing the control unit should be left to a specialist workshop, as the airbag system should not be worked on yourself.

Then create a repair order online and send in the control unit. Processing usually takes 3–4 working days: checking, repairing and testing. The repaired control unit comes back with all vehicle data and is ready for use immediately after reinstallation — coding or programming is not necessary.