Light-Duty Vehicles
The concept of defeat devices in the case of Light-Duty vehicles (LDV) is delineated in Article 3(10) of Regulation (EC) No 715/2007:
‘‘defeat device’ means any element of design which senses temperature, vehicle speed, engine speed (RPM), transmission gear, manifold vacuum or any other parameter for the purpose of activating, modulating, delaying or deactivating the operation of any part of the emission control system, that reduces the effectiveness of the emission control system under conditions which may reasonably be expected to be encountered in normal vehicle operation and use;’
The prohibition to use defeat devices and exceptions is specified in the same Regulation, Article 5(2):
‘The use of defeat devices that reduce the effectiveness of emission control systems shall be prohibited. The prohibition shall not apply where:
(a) the need for the device is justified in terms of protecting the engine against damage or accident and for safe operation of the vehicle;
(b) the device does not function beyond the requirements of engine starting;
or
(c) the conditions are substantially included in the test procedures for verifying evaporative emissions and average tailpipe emissions.’
The prohibition, however, must be considered in conjunction with the regulations stipulated in Commission Regulation (EU) 2017/1151, particularly concerning the utilization of Auxiliary Emission Strategies.
The pertinent definitions are specified in Regulation (EU) 2017/1151, Article 2:
’43. “base emission strategy” (hereinafter “BES”) means an emission strategy that is active throughout the speed and load operating range of the vehicle unless an auxiliary emission strategy is activated;
44. “auxiliary emission strategy” (hereinafter “AES”) means an emission strategy that becomes active and replaces or modifies a BES for a specific purpose and in response to a specific set of ambient or operating conditions and only remains operational as long as those conditions exist.’
And Article 5 (11):
‘In order for the approval authorities to be able to assess the proper use of AES, taking into account the prohibition of defeat devices contained in Article 5(2) of Regulation (EC) No 715/2007, the manufacturer shall also provide an extended documentation package, as described in Appendix 3a of Annex I to this Regulation.’
The approval authority may test the functioning of AES.
A list of AES which were deemed non-acceptable by type approval authorities shall be compiled yearly by the Forum for Exchange of Information on Enforcement and made available to the public by the Commission at the latest by end of March of the following year, in case there were AES which were deemed non-acceptable.
The manufacturer shall also provide to the approval authorities a formal documentation package, as in Appendix 3a to Annex I, containing information on AES/BES that would allow an independent tester to identify if the emissions measured can be attributed to an AES or BES strategy or are potentially due to a defeat device. The formal documentation package shall be made available to all type approval authorities, technical services, market surveillance authorities, third parties and the Commission upon request.
In accordance with Annex IIIA of Regulation (EU) 2017/1151, the following provision is applicable:
‘4.4. If for a vehicle the collection of ECU data influences the vehicle’s emissions or performance the entire PEMS test family to which the vehicle belongs as defined in Appendix 7 shall be considered as non-compliant. Such functionality shall be considered as a “defeat device” as defined in Article 3(10) of Regulation (EC) 715/2007.’
Heavy-Duty Vehicles
For Heavy-Duty Vehicles (HDV), the concept of defeat strategy is elucidated in Article 3(8) of Regulation (EC) No 595/2009:
“defeat strategy” means an emission control strategy that reduces the effectiveness of the emission controls under ambient or engine operating conditions encountered either during normal vehicle operation or outside the type-approval test procedures;
In the context herein, the term "defeat devices" is to be interpreted to encompass defeat strategies for Heavy-Duty Vehicles (HDV) as well. The prohibition against the use of defeat strategies is specified in the same Regulation under Article 5(3) of Regulation (EC) No 595/2009:
‘The use of defeat strategies that reduce the effectiveness of emission control equipment shall be prohibited.’
A notable distinction between the two regulations lies in the fact that, for LDV, exceptions are specified for defeat devices, whereas for HDV, exceptions are outlined in relation to the utilization of AES. This information is found in UNECE Regulation No. 49 (8), Revision 6, Annex 10, paragraph 5.1.2:
‘An AES shall not reduce the effectiveness of the emission control relative to a BES under conditions that may reasonably be expected to be encountered in normal vehicle operation and use, unless the AES satisfies one the following specific exceptions:
(a) Its operation is substantially included in the applicable type-approval tests, including the off-cycle test procedures provided for in paragraph 6 of Annex VI to this Regulation and the in-service provisions set out in Article 12 of this Regulation (9).
(b) It is activated for the purposes of protecting the engine and/or vehicle from damage or accident;
(c) It is only activated during engine starting or warm up as defined in this annex;
(d) Its operation is used to trade-off the control of one type of regulated emissions in order to maintain control of another type of regulated emissions under specific ambient or operating conditions not substantially included in the type approval or certification tests. The overall effect of such an AES shall be to compensate for the effects of extreme ambient conditions in a manner that provides acceptable control of all regulated emissions.’
