Which data do OEMs collect from connected cars?

June 01, 2016 // By Christoph Hammerschmidt
In modern cars, dozens of computers and hundreds of sensors continuously generate, store and transmit data. Only the car manufacturers know what are those data. Based on the example of three vehicles – Mercedes-Benz B-series, BMW 320d and i3 as well as Renault Zoe - the German motor club ADAC has examined which data are sent to the manufacturer.

The investigations show that OEMs collect a wealth of data that allow drawing conclusions on the health status of many car systems, but also on the usage profile and driving behavior of the driver.


The Mercedes-Benz B-series transmits, for example, every two minutes the vehicle’s mileage, fuel level, coolant level and tire pressure. While these data may have some relation to the health status of the vehicle, Daimler is also nosy in things that are at least questionable like how many times the belts have been tightened (as the result of an emergency braking) or the GPS position. In addition, the car stores mileage in city traffic, country roads and motorways separately, enabling the OEM to create a usage profile.


In the Renault Zoe, the ADAC experts found that the OEM can access the vehicle remotely via mobile connection and read out any desired data from the CAN bus. This remote diagnostics option is deactivated by default but can be activated at any time remotely. The car also transmits at least every 30 minutes a data packet containing several serial numbers, time stamp, GPS position, temperature and state of charge of the high-voltage traction battery. In addition, the manufacturer can request this data packet at any time. He also can change to composition of the packet via wireless connection. What’s more, the OEM can inhibit charging the batteries, for instance in the case of an unpaid leasing rate.


The data from the BMW 320d (which has already been examined in 2015) and Mercedes B-class are rather similar, though there are differences resulting from the different equipment attributes of the two vehicles tested. BMW acquires data from wearing parts and components, in particular in engine and transmission. Privacy-relevant data are generated in the head unit in the first place, in particular in cases where the driver uses to link his smartphone to the head unit. Across the mobile