L-category vehicles shall be equipped with an OBD system which complies with the functional requirements and test procedures as laid down in the delegated acts adopted pursuant to paragraph 5 and as from the application dates as set out in Annex IV.

From the dates set out in point 1.8.1 of Annex IV, vehicle (sub-)categories L3e, L4e, L5e-A, L6e-A and L7e-A shall be equipped with an OBD stage I system which monitors for any electric circuit and electronics failure of the emission control system and reports those failures which result in the emission thresholds as laid down in Annex VI (B1) being exceeded.

From the dates set out in point 1.8.2 of Annex IV, vehicle (sub-)categories L3e to L7e shall be equipped with an OBD stage I system which monitors for any electric circuit and electronics failure of the emission control system and which is triggered when the emission thresholds as laid down in Annex VI (B2) are being exceeded. OBD stage I systems for these vehicle (sub-)categories shall also report the triggering of any operating mode which significantly reduces engine torque.

From the dates set out in point 1.8.3 of Annex IV and subject to Article 23(5), vehicle (sub-)categories L3e, L5e-A L6e-A and L7e-A shall in addition be equipped with an OBD stage II system which monitors and reports emission control system failures and degradation which results in the OBD emission thresholds as laid down in Annex VI (B2) being exceeded.

In order to harmonise the OBD system reporting of functional safety or emission control system faults and facilitate effective and efficient repair of a vehicle, the Commission shall be empowered to adopt delegated acts in accordance with Article 75 concerning the detailed technical requirements related to on-board diagnostics, including functional OBD requirements and test procedures for the subjects listed in paragraphs 1 to 4 and X1as referred to in Annex II (C1) 11 and test type VIII referred to in Annex V.