Judgment of the Court (Second Chamber) of 17 December 2020.#CLCV and Others (Defeat device on diesel engines).#Request for a preliminary ruling from the Juge d'instruction du tribunal de grande instance de Paris.#Reference for a preliminary ruling – Approximation of laws – Regulation (EC) No 715/2007 – Article 3(10) – Article 5(2) – Defeat device – Motor vehicles – Diesel engines – Pollutant emissions – Programme acting on the electronic engine controller – Technologies and strategies to limit the production of pollutant emissions.#Case C-693/18.