The black box in the passenger car becomes mandatory

From July 2024, all new cars must have an event data recorder in the vehicle that stores vehicle data directly before and after a crash. This is a requirement of an EU regulation.

Aircraft have a black box from which events before and shortly after a crash can be read. Such a device will also be used for cars in the future: The so-called Event Data Recorder (EDR) records a short period of time before and after the crash.

Many vehicles are already equipped with an EDR - completely new models have even been required to have one since June. From July 7, 2024, the black box will be mandatory for all newly registered passenger cars. According to the ADAC, the main task of the EDR is to gain a better understanding of an accident through the data recorded in the process.

The EDR is usually installed in the airbag control unit, as this is where all the relevant information from acceleration sensors comes together - this information is also used to trigger the EDR's data recording. Data such as speed, engine speed, steering angle or whether the airbag was triggered are recorded. The recording is triggered in a time window of five seconds before and 300 milliseconds after the crash.

No OTA data transmission possible

The data is stored locally in the vehicle and remains there. It cannot therefore be transmitted "over the air" via an online connection, so that it does not fall into the hands of third parties. With the help of certain tools, they can be read out via the OBD interface or directly at the airbag control unit.

The aim is not to clarify the question of guilt

For example, EU Regulation 2019/2144 literally states, »This data recording should allow data to be recorded and stored in such a way that Member States can use it to carry out road safety analyses and evaluate the effectiveness of specific measures taken, and the stored data cannot be used to identify the user or keeper of a particular vehicle.«

According to the regulation, the last four digits of the vehicle identification number as well as information on the owner or holder may not be recorded, stored or even passed on when the data is sent. This also applies to partially or fully autonomous vehicles in the future.

Data protection versus penal interest

However, the ADAC believes it is possible that the interest in criminal prosecution will be weighted higher than the interest in individual data protection. In this case, the driver or owner of the vehicle would not be able to prevent the EDR data from being read out. This could be the case, for example, if it has to be clarified how an accident with serious injuries and fatalities came about.

Under data protection law, the sovereignty of the data from the DER lies with the driver or owner. However, in order to find out how an accident occurred in connection with civil or criminal proceedings, a court or the public prosecutor's office can commission an expert to read out the data from the EDR.

However, according to the ADAC, the data from the EDR should not be used as the sole source for accident reconstruction. Rather, they serve as an additional element to the trace image at the scene of the accident and the damage to the vehicles involved. Thus, they can support the conventional reconstruction of an accident, but not replace it. The EDR only stores data about the driver's own vehicle and not about other road users. Video recordings are also not possible with it.

When does the Event Data Recorder trigger?

The EDR is triggered when it registers a change in speed in the transverse or longitudinal direction of more than 8 km/h within 150 milliseconds, when seat belt tensioners or airbags are triggered, and when an active hood is triggered. The latter would be the case, for example, in the event of a collision with a pedestrian.

The device only stores data that is of interest in the event of an accident. This includes vehicle dynamics data before the crash, such as speed, engine throttle/gas pedal position and brake status, vehicle dynamics data after the crash, such as speed change in longitudinal and lateral direction, as well as information on restraint systems, such as seat belt status of driver and front passenger or deployment time of the airbags for driver and front passenger.