This judgment could be expensive for Volkswagen: The ECJ makes it clear that defeat devices in diesel cars are illegal if they allow higher emissions of pollutants “for a major part of the year”. National courts decide whether this is the case in individual cases.

Under certain circumstances, Volkswagen has to take back diesel cars with so-called defeat devices from its customers. The European Court of Justice (ECJ) has made it clear in a judgment that software that allows higher emissions of pollutants “for the majority of the year” is fundamentally inadmissible. National courts must now examine whether this is the case in specific cases.

The background to the judgment are three cases heard before Austrian courts in which VW cars were equipped with switch-off software, a “thermal window” (cases C-128/20, C-134/20, C-145/20) . According to the ECJ, some of this software permitted emissions of nitrogen oxides that were higher than the EU limit values ??permitted. According to the national courts, this was the case at temperatures below 15 or above 33 degrees Celsius. VW speaks of temperatures below 10 degrees. For exhaust gas cleaning in diesel, some of the exhaust gases are fed back into the engine and burned again.

According to the Court of Justice, the EU regulation applicable to the cases under discussion provides that consumers can request repairs and a replacement of the car, provided that this is not impossible or disproportionate for the company. However, under certain circumstances, customers can also request a price reduction or termination of the contract. This is the case if the seller does not remedy the situation within a reasonable time or without significant inconvenience for the consumer, as the ECJ announced.

After the decision, the car manufacturer Volkswagen stated that it saw its legal opinion confirmed: “According to the criteria set out by the ECJ in its judgment, the thermal windows used in vehicles of the VW Group remain permissible.” They protected against immediate risks to the engine in the form of damage or accidents.